I should have stated that my MacPro is the previous version of RAM (before Nehalem).
For what it's worth, I held off my MacPro for 18 months, waiting for Nehalem. Apple dragged its heels. Then, four weeks after I ordered my MacPro, they released Nehalem. Aarggggggg, so so frustrating. At least my MacPro offers a Firewire 400 port, and doesn't use the new small display port (I am running a NEC3090).