When the 2010 RC was released I installed it to replace the Beta2. An on top of that I installed the Team Explorer that was released at the same time. That is not the way to go! The Team Explorer is now already included in Visual Studio 2010 RC Ultimate and there is no need to install it separately as you had to do with earlier versions of Visual Studio.
In fact you should NOT install it. The Team Explorer install makes Visual Studio behave strange when you do this. When I build setup applications (web applications in this case to be exact) Visual Studio displays a dialog telling you:
“Please wait while Windows configures Microsoft Visual Studio 2010 Shell (Integrated) – ENU…”
And it takes a long time to build the project. Like 10 minutes instead of 30 seconds.
The solution is to uninstall the Team Explorer.
This is the only issues that I have seen with this, it might be the only thing or there might be more, I do not know. But this behaviour is confirmed by MS and they will have it fixed in the RTM version.