I just signed up to add my $.02 on the wandering topic. 🙂 We use VMWare extensively here and had positive results. I looked into Hyper-V using SCOM (similar to vCenter) but it required too much effort to replicate something we already have and invested with VMWare/vCenter. When I have time, I do need to look back again though. And just like what OP said, VMWare does offer support for various platforms and we run them all (Windows, Linux, Solaris). Now we're looking to virtualize the Mac platform using a Mac Pro.
Anyway, I came across this thread because I wanted to know since Apple only configures its Mac Pro to a max 64GB, I guess the only option is to go 3rd party vendor/supplier?