I'm not sure it's such a slam dunk -- a brief scan of the virtual machine benchmark didn't seem to have a more heavily concurrent load. Plus the Opterons are substantially cheaper.
If I was building a server I'd probably look at the Intel parts, the cost/performance curve is justifiable. But my personal case right now is running lots of test VMs simultaneously on a workstation, the Opterons are more attractive.
I should probably have linked to Sandy Bridge EP vs Bulldozer, which is much more lopsided. The 6C holds its own nearly everywhere, with comparable price and much lower power usage, and there's always the option of bumping up to 8C when needed:
If I was building a server I'd probably look at the Intel parts, the cost/performance curve is justifiable. But my personal case right now is running lots of test VMs simultaneously on a workstation, the Opterons are more attractive.