I don't want to start a flame war here, i just was on AMD's website and found this video. IT compares the AMD Opteron and the Intel Xeon CPUs. Its enlightening, cheesey, and amusing. Again, I AM NOT TRYING TO START A FLAME WAR.
http://enterpriseevent.amd.com/amd_05e4/dcdvideo/high.html
http://enterpriseevent.amd.com/amd_05e4/dcdvideo/high.html