i7 or i5 for Virtual Machines

If you get the quad-core i5 760 then you're good - the only difference with the i7 is the Hyperthreading which I don't think makes much of a difference with VMs.

RAM is the big thing here. 8GB should be OK, but the money you'd save on sticking with the i5 should give you a big boost up to 16GB - plenty of 16GB kits on Newegg $200-$300

The link is broken.

May I suggest an SSD? It will make a difference.
In that case do not defrag your VM OSes even if VMWare recommends it.

Yeah, I have an i7 and have plenty of VM's. I only have 6GB of ram though so I run usually 1-2 at the same time, but my the performance seems excellent.