I'm having a very mixed experience with VS2005.
The look is nice, aside from the toolbars, which just look dull. (Why does Microsoft have this compulsive need to invent a new way to render toolbars every year?) I really like the new Start Page over the VS2003 launch mode. The installation was fast (compared to VS2003) and easy, without any weird Prerequisite steps. One thing I never understood about VS2003 was why the Prereqs CD has to be run first even though the "Disc 1 - Install" CD says to put it in first. Seems like a silly oversight, and at least that kind of goofiness is gone in 2005.
Other than that, though, I hate it so far. The install failed to properly register solutions to open in VS2005, so all my code tries to open in VS2003, which of course can't read the new solution files. The new "Repair File Assocations" feature is nice, but didn't work - .sln files remain stoically associated with VS2003. I had to do some manual registry tweaking to get that to go away.
So once I could actually open solutions, I went to do some compile testing to see how things look. I had to do some twiddling with Include and Library paths, which is somewhat to be expected with all the SDKs I use, although I must say I'm disappointed that nobody at Microsoft has yet realized that they can import my old settings. Every time I upgrade VS, I dream that I won't have to redo all of my personalization. Every time, I'm disappointed.
I had to go back through all the menus, toolbars, and little tear-off panes and arrange them the way I like. I can understand some things not being importable from prior versions, but it's just a nuisance to have to redo all of it. That's all one-off migratory pain, though, which I'm willing to let slide, disappointing though it may be.
The real kicker is that IntelliSense now sucks. Approximately every 2 minutes, VS2005 will "Update IntelliSense." This process takes about 35 seconds to a minute on a project the size of the one I'm working on, and totally pegs the CPU for the duration. It doesn't background it, doesn't thread it to keep it from deadlocking VS - the entire IDE is dead and the rest of my system is sluggish until the update finishes. There is no button or key that will cancel it as near as I can tell.
As if that wasn't bad enough, it also does this spontaneously during builds. What the HELL, Microsoft? How can you not think to disable CPU-intensive tasks during a build? I can't even change build settings for other build configurations while a compile is going on, but somehow it slipped your minds that "updating IntelliSense" during a build is really stupid?
But wait! It gets even better! About 60% of the time, this "update" process totally kills VS. That's right - dead. Locked. Frozen. Kaput. Open task manager again, end process. This has apparently already been investigated and fixed according to the public VS bug tracker. The "workaround" is to remove a DLL so that the entire IntelliSense subsystem fails to run. Err... sorry, no, that's not going to cut it. I may as well use Notepad at that point. IntelliSense controls statement completion, class hierarchy generation, and apparently a bunch of other stuff, because disabling it basically turns VS into a glorified brick.
I want to like VS2005. I really do. Hell, I want to love it. The function caller/callee diagramming stuff is just awesome, and the OpenMP support is very much important for our future plans.
Sadly, though, until we get SP1, I think I'm going to be forced to hate it.