I successfully installed Windows 7 RC and Visual Studio 2010 Beta 1 on WMware Fusion on my MacBook without a hitch. Mind you I have only been playing with it for a couple of days so there may be some gotchas sitting around waiting for me to hit them.
Although VMware Fusion does not officially support Windows 7 RC, I downloaded the ISO and installed it like any other version of Windows. The VMware Fusion Team Blog has a step-by-step procedure for creating a new virtual machine for Windows 7 here.
I then went ahead and installed Visual Studio 2010 and .NET Framework 4.0 beta. All went fine. I received the expected compatibility issue with SQL Server 2008 and followed the appropriate actions by installed SQL Server 2008 SP1. I installed Visual Studio 2010 Team Suite but you can also install Visual Studio 2010 Professional.
You gotta love being able to run Windows 7 via VMware Fusion on the Mac.
Good Luck!
David Hayden