I've never run Windows on any of my Macs prior to installing Win7 on my MacPro the other day. I used Bootcamp; I'm running Win7 from a dedicated 500gb hard drive (by design; I didn't want either OS to see the other in an effort to have maximum security until I've had time to sort out the perils of running Windows again from a security standpoint). Here's the deal: Win7 is pretty good, and there are a few Windows apps I've been wanting to run (VB/macro-enabled Excel is one). It's a bit of a pain to have to boot one or the other, so I'm intrigued with trying VMware Fusion 2.0, but I'm unclear as to how it works. I don't think I want Win7 running in a virtual machine if that means 1) my drives will be able to see/talk to each other in a way that compromises security, or 2) performance will be compromised. I'd rather put up with the inconvenience of booting separately if either of these are going to be significant. My MacPro configuration is as follows: 2008 quad-core 2.8ghz processors w/ 10GB of RAM; 250GB HD with Mac OS X; 500gig HD, OS X extended, for Mac stuff; 500gig NTFS HD devoted to Windows; external 1TB Firewire drive for backup; external 250GB Firewire drive for backup redundancy on certain files. I like the idea of being able to hotswitch; what do you guys think?