thanks thomas!! any idea regarding rhel 5? i'd assume that centos (5) would be out shortly thereafter as well...
RHEL 5 is slated for a December release, depending on feature completeness and quality.
I don't know about CentOS's release cycle. IMHO, even though they are technically true to the letter of the GPL, I think that they do is a blatant ripoff of all the hard work that Red Hat does in creating FC and then RHEL. If you want RHEL, spend the bucks and get it. It is not expensive, WS is only $179 and it contains everything you will need for a workstation. If you want a true server build, ES is $349 and that is still cheap.
See https://www.redhat.com/apps/commerce/ for pricing and details, and see http://www.redhat.com/rhel/ for links to comparisons of features and functions.