Since 2008 I've been running and OEM System Builder copy of WinXP in VMWare Fusion that I got at my local Frys. In early '11 when I bought my MBP I used migration assistant to set up that machine and to my surprise, it also imaged my WinXP virtual machine. That's where I stand today. Since most of my clients are now running Win7, I thought I'd join the crowd. I'm thinking about going to the OEM System Builder route again and getting Win7 Professional but the question is should I purchase the 32bit or 64bit version? Are there any things I should be aware of when running this OS with VMWare or on the machines I have? BTW, I'm running Fusion v5.0.2 on both machines.