I have to say after installing Visual C# 2008 Beta 2, Visual C# 2005 is useless. Why? Because I am using Vista Home Basic on which Visual C# 2008 performs better.
For example, Expert Manager in CBC needs elevation. In Visual C# 2005 I have to manually add a manifest file (using mt.exe in SDK). In Visual C# 2008, it is nearly automatically.
Compared to Visual C# 2005, Visual C# 2008 no longer needs elevation at startup (this is a nice change). And at this moment, I do not notice other improvements because I am working at Windows Forms, not AJAX, Silverlight, or WPF.
I have found some bug in Visual C# 2008 too. When you try to clean a project as usual, you found some .tmp files cannot be removed (UAC turned on). I guess they are generated by AutoRecover feature. Wish I can find a way to remove the files at last.
In all, Visual C# 2008 is better than Visual C# 2005.
(Updated: Yesterday when I powered on my computer, I found that I could use Clean task of *.sln file to remove those .tmp files. So I guess the rule is “you cannot delete them until you wake up tomorrow”.
Now I turn off AutoRecover feature completely, and find no .tmp files any more. They are gone! at last!
Also it is fun to report bugs to Microsoft. Thanks to Scott, Omar, and DJ.)
(Updated Again: Even if I turned off AutoRecover, new temp files were still generated. Luckily, they did not prevent me from developing so I try my best to ignore their existence.)