There is a recent review (late 2005, I think) that put Intel's latest Xeon against Opteron again and the Opteron stomped it with no problem in almost every category.
Here are some other links to Opteron vs. Xeon reviews:
April 22, 2003 - Dual of the Titans
http://www.tomshardware.com/2003/04/...ans/index.html
March 2, 2004 - AMD Opteron vs. Intel Xeon: Database Performance Shootout
http://www.anandtech.com/IT/showdoc.html?i=1982
Aug. 13, 2004 - Workstation showdown: Xeon vs. Opteron
http://www.infoworld.com/article/04/...station_1.html
Sept. 13, 2004 - Intel Xeon 3.6 (Nocona) vs. AMD Opteron 250 - Dbase Test
http://www.anandtech.com/IT/showdoc.aspx?i=2205
I'm still looking for the latest shootout I read a few months back where AMD openly (In 100's of newspapers across the USA) challenged Intel to put up or shut up. Intel finally delivered one of their new Xeons and the Opteron that was not even their latest hot thing spanked it.
With the NUMA standard and utilization of hyper-transport Intel is just out of luck and I don't forsee that changing any time soon. AMD is far ahead in chip architecture.