Phoronix: CentOS vs. Oracle vs. Scientific Linux 6.1 Performance

While CentOS, Scientific Linux, and Oracle Linux Server are all derived from the same upstream source (Red Hat Enterprise Linux), how does the system performance compare between these RHEL derivatives? Here are some benchmarks of each of the 6.1 releases for Oracle Server, CentOS, and Scientific Linux, as they all do not perform the same.

http://www.phoronix.com/vr.php?view=16835