hello, I was not able to wait before buying a mac pro, so I had to buy the latest model 2012, which have not been many improvements since 24 months.
Still, this is an excellent machine.
Here's my test:
Last Mac Pro 2012
Lion 10.7.4
2x2, 4 GHz - 6 Core Intel Xeon - 12 cores active
12 GB
ATI 5770
KeyShot 3.2.36 - fps: 88
I am happy, but poor ...
Here we clearly see that KeyShot uses all available cores of the Mac.
Antoine