Will report on features, stability etc. soon.

Update (17:41 GMT+2): I've been using ReSharper 2.0 build 201 for a few hours now, and have come to the following conclusions:

• It is drastically slower than 1.5 (build 162) I've been using for a while now.
• Despite claims to the contrary, the preprocessor still sucks big-time; large parts of the codebase I'm currently working on heavily depend on preprocessor directives (mostly #if, #else, #elif) and ReSharper goes haywire parsing them. This also leads to:
• Extremely buggy autocompletion behavior, to the point where it completely fails to display some superclass members, where in 1.5 (despite preprocessing issues) it worked perfectly.
• Takes an inordinate amount of memory.
• Crashes repeatedly.
• Bottom line, removed in favor of 1.51 (beta build 165); I'll try updated builds as they come out and report.

Update (August 1st, 10:42 GMT+2): I've been using the newer build 202 for a few hours now, and it does seem quite a bit faster and certainly more stable; it's still not as fast as 165 (particularly as far as initialization time is concerned) and I've encountered a few quirks here and there (at one time ReSharper quite simply refused to recognize the referenced assemblies - even .NET-intrinsic ones) and some minor usability issues, but it's a major improvement over 202. Some of the improvements over 165 are also marked, in particular the 'error/warning bar' on the right feels more robust and the code formatting template is far more customizable (although admittedly I haven't looked at this since 152, I could be wrong - and anyway it's not yet as impressive as Eclipse's). Can't wait for 203, I've no idea where I would be without ReSharper...

Update (August 3rd, 17:43 GMT+2): Tried installing build 203; the RFE I filed has apparently been taken seriously and sorted out, however the new build completely screwed up the intrinsic Visual Studio shortcuts; Ctrl+Tab and Ctrl+F4, for example, wouldn't work with 203. I tried removing ReSharper and installing anew, created a new keyboard profile from the defaults etc., but it was all in vain and the absolutely necessary shortcuts I mentioned would not function. Eventually in desperation I went back to 202 and filed a bug report (which doesn't seem to show up, but nevermind that). Hope this gets sorted out quickly. I've also found that the default Shift+F6 shortcut for renaming items has been changed to F2; I'm not sure which was the first version to feature this change (202 does though), but changing default key bindings suddenly after years of sticking with the same profile is a nasty thing to do.

Update (August 11th, 15:37 GMT+2): During the last few days I've been working intensely with three seperate development machines. The main machine at work had ReSharper build 202 on it, the other two build 165, so basically for a couple of days I went back to 1.5. My conclusions? 2.0 is much better feature-wise (better refactoring capabilities, improved UI, parsing and code reformatting), but it is currently dramatically slower in both boot and runtime performance. Also, at some point build 202 simply went haywire, refusing to recognize namespaces in referenced assemblies even for new Visual Studio-generated WinForm applications. In frustration I removed it and went back to 165. In the meanwhile the shortcut bug I reported for build 203 was fixed (although 204 isn't out yet...), and I've also reported a usability issue.

Update (August 12th, 15:21 GMT+2): I've been using build 204 for a couple of hours now. It seem to have solved the keyboard issue and is also a bit faster, however the problem I reported with 202 going haywire is even more pronounced in this build. I've filed a bug report and hope to see it resolved soon (because currently it's almost impossible to work with it for new projects where you keep adding/changing references).

Update (August 16th, 15:41 GMT+2): After using build 204 intensely for a couple of days I've come to the conclusion that it simply isn't fast/stable enough for proper development and am revering to 165. I'll keep testing 204 at home (and include, at JetBrains' request, Visual Studio 2005 in my tests), hopefully I'll be able to help them track down the external reference bug. That said, a usability bug I've filed a week or so ago remains open; if you have anything to add it might help the ReSharper guys reach a better/quicker decision about it.

Update (August 21st, 11:30 GMT+2): Build 205 is out. They've fixed a couple of bugs I filed (including public ovveride and immediate window autocompletion issues). No news about the external references issue (partially my fault because I still haven't tested VS2005, but I still don't see what 2005 has to do with it...). I'll try it out this morning and post updates.

Update (September 8th, 16:56 GMT+2): I've been testing build 206 for a few hours now. For the first couple of hours it felt a lot faster and more solid than any of the earlier builds, and the inclusion of a multiple-entry clipboard handler (Ilan Asayag's RFE) should be very useful although I haven't tested it; however, there is a major bug in the new parser which completely barfs on one of the projects I work on and simply hangs Visual Studio 2003 on 100% CPU utilization endlessly. I've filed a bug and we'll see what happens; in the meantime I'm reverting back to 165 (in whose parsing engine I've also found and filed a bug - it does not process lock statements properly).

Update (September 26th, 12:13 GMT+2): Initial impressions from build 207: it is a lot faster and a lot more robust than the previous builds, however it still barfs on the source file I mentioned on 206. I'll get in touch with JetBrains and try to find out what's up.

Update (November 2nd, 16:49 GMT+2): I've been working with 208 for a while now but couldn't find the time to post anything about it. Let's skip to 209 then: I've replaced 208 in a production environment with 209. Yes, 208 has already been stable enough to work on real code with; in fact it's so far been a pleasure. The guys at JetBrains are doing very impressive work on this product. Now that most of the bugs are squashed, though, they should get to work on optimizing the codebase a little bit; VS2003 startup times are noticeably slower with ReSharper 2.0 installed (not that they aren't horrible to begin with) but text editing can at times grind to a crawl even on a decent system. I'll try to find a way to shout out so that this request is heard. Please do the same; Eugene and the other guys at JetBrains really do listen to customers, so if enough people request it I reckon they'll get the hint.

Update (December 7th, 18:24 GMT+2): 210 has been out for a couple of weeks now and seems quite stable. I do have a couple of issues with it, though: first, performance hasn't improved at all since 208, and I have a bizarre issue where R# hogs the Ctrl+D shortcut (which I have permanently assigned to GhostDoc), and reassigning it to GhostDoc doesn't seem to work. R# is worth more to me (productivity-wise) than GhostDoc so I'm willing to suck it up for now in hopes that the guys at JetBrains sort it out by the next release.

Update (December 25th, 18:02 GMT+2): Skipped right to build 213. It seems that there are few differences between versions on VS2003, because although Ayende reports it to be horribly buggy with VB.NET (presumably with VS2005), I've encountered no new issues. R# doesn't seem to handle source control providers properly though - we use Vault at work and R# chokes whenever I edit a file that hasn't been checked out yet (update December 28th, 12:40: apparently JetBrains fixed the bug for build 214, I'm looking forward to it).

Update (January 3rd, 20:42 GMT+2): Lost some more work when my ISP went down and Firefox's bizarre clipboard issues popped up again. I'll have to file a bugreport on that as well. Anyways a quick recap of what was in the earlier (lost) update: bug #14980: Problematic integration with source-control not yet solved (was supposed to have been fixed but I reopened it). Bug #15702: Highlighting options not retained vanished in the new build, although it's not officially fixed. Bug #13866: ReSharper does not relinquish keyboard shortcuts? appears not to have been a bug (see link for explanation) but bug #10851: Can't use Enter on "override" autocomplete popped up again. The asynchronous startup doesn't seem to work (either that or it's not supported in VS2003) although I'm not sure what to look for, so it's not a bug per se. Finally I've filed a few feature requests, go ahead and vote.

Update (January 4th, 12:39 GMT+2): Build 214 is off my machine. It has way too many bugs to be really useful; at some point the project I was working on started exhibiting odd static code errors which didn't seem to make sense; after a while the build 214 parser went completely haywire and refused to recognize namespaces even local to the project. Deleting the caches etc. didn't do any good so I eventually reinstalled 213. Additionally I've finally started using VS2005 at work, hopefully I'll have more insight into R# now (I'll start a new post regarding R# on VS2005 when I have something to report).

Update (January 29th, 19:38 GMT+2): Been using build 215 for a little while now. It's a great deal more stable than 214 and also fixes a few bugs, but isn't nearly as stable as 213; exceptions are in abundance and sometimes it just seems to "flip out", requiring a restart of the IDE to return to normality. I'm not sure what's changed since 210, but since there are no major new features obviously some rewrite or another caused some severe regression issues. I'm this close to going back to 213, I'll give it a few more days and if 216 isn't out by then I'll do just that.

Update (February 12th, 16:42 GMT+2): Skipped 216 and went right to build 217. It fixes a lot of issues I had with 215 (far less exceptions, for starters, but there are still issues and bug #15702 still isn't fixed). It also feels a lot more responsive, but it's difficult to judge since I changed to a considerably faster workstation at work. I've also started using VS2005 along with VS2003, which makes these reports a little more useful (I think?).

Update (February 12th, 19:52 GMT+2): The initial impression of stability was apparently misplaced. A certain exception keeps popping up all over the place after an hour or so of use (a parser bug by the look of it); I would rate this as a show-stopper bug and recommend you keep away from this build. I'll try downgrading to 216, and if all else fails 215, but I do hope they fix this as soon as possible because this is an otherwise excellent version.

Update (March 2nd, 2006, 22:13 GMT+2): While builds 217 and 218 were disappointing, 219 is so far a pleasure to work with. It's very stable and seems to have got rid of most of the annoying bugs (in particular #14980). Also, feel free to vote or comment on any of the open issues I posted (#16662, #10855 , #18447, #18660, #12531).

Update (March 2nd, 2006, 22:23 GMT+2): Bah, as usual, I spoke to soon. Be very careful with 219 if you do any editing on XML schemas; for me it went haywire with exceptions all over the place and eventually crashed Visual Studio 2003 entirely.

Update (March 7th, 2006, 17:10 GMT+2): Tested build 220 for about two hours. It's riddled with bugs; I've filed at least four different exception reports in that period of time. Back to 219 for the moment.

Update (March 9th, 2006, 15:32 GMT+2): Build 221 is not perfect, but for the most part is very usable. I've encountered a couple of odd exceptions (in fringe cases); generally speaking it's not as stable nor as fast as 219, so if you have that installed I suggest you stick with it.

Update (March 12th, 2006, 14:46 GMT+2): I've been heavily developing with 222 for a few hours now and it's very buggy. I've been getting random exceptions (and even exceptions from the bug submission service!) and although it feels faster than 221 stability is lackluster. I would recommend to stick with 219 for now.

Update (March 14th, 2006, 11:39 GMT+2): Build 223 is quite usable, although a far cry from the stability of build 219. I've already encountered numerous exceptions and there's a certain source file which throws the parser into an infinite loop. JetBrains could use some more regression testing, but I guess that's what the EAP's all about.

Update (April 10th, 2006, 17:02 GMT+2): Been a while and ten builds since my last update. I'm happy to say that I've been working with 232 with both Visual Studio 2003 and 2005 and it's been almost rock stable so far (I've only encountered one bug with an intermittent "can't edit read-only file" issue I've already reported to JetBrains). I'll update to 233 and post my experiences with that build soon.