Bear Feats has done a benchmark comparison of the Dual G5, P4, Dual Xeon, and Dual Athlon systems, and in all but one test the G5 came out on top. The one test that the G5 didn't come out on top was a comparison between the G5 2.5 and Xeon 3.06, where the Xeon beat out the G5 by 6 points. So I'd say the G5 actually won out on that test as well, since its not clocked at 3Ghz just yet.