Since I installed Win2008 on my Mac I never really used it: turning on my company's laptop was less painful than the usability problems that both VMware and Parallels have.
VMware was not working very well with more than one display: if you open an application in Unity mode it will be stuck in the display the main Fusion application is running, and in fullscreen mode it is not possible to have more then one display.
Parallels works fine with multiple displays, but I don't like the way the mouse pointer is handled in Coherence mode: there are 2 pointers, with the one inside the Windows application that mimics the movements of the mac one.
Watch the movie, with an astonishing 8 displays being supported!!
Now I think I can really start thinking of using my mac for everything, including developing on Visual Studio.