In the article mentioned below, Tyan, the maker of high end motherboard products says:

Tyan will provide customers a choice of two platforms, AMD Opteron and Intel Xeon. When asked about which platform better fits which sort of task, the company answered that Opteron is the optimal choice for memory-intensive applications, but Xeon processors beat Opteron in terms of performance measured in FLOPS (floating-point operations per second).

http://www.digitimes.com/systems/a20051124PR200.html

I thought that the Opteron was better all around for any computing function versus the Xeon but after looking at some of the Xeon work unit output rates I'm starting to believe that may be the case.

I was looking at the host stats for this project:

http://www.boincstats.com/stats/host_stats.php?pr=wcg&st=0&to=100

and I'm getting the feeling that the Xeon might be outperforming most any other cpu when it comes to floating point operations.

The World Community Grid application uses floating point operations intensively, yes?