Mac Pro firmware update
Apple has issued a firmware update for the Mac Pro Nehalem (see my review especially for photographers). You can use Software Update to update firmware.
Firmware updates always concern me, but I updated both my 8-core 2.93GHz and 4-core 2.66GHz Mac Pros without a hitch. It takes a few minutes.
Both of my Mac Pros use an SSD boot drive, and the 8-core has 64GB memory. No problems.