My most recently activated license for RHEL expired within the last two or three days. I may have an unused license stashed somewhere, but I've been planning to migrate to some other distribution of Linux when this one expired, because I've been so unhappy with Red Hat's past ill-preparedness for demands upon their servers at times of new releases.

Gaal once suggested that I try a flavor of Linux, such as Ubuntu, that used a more-advanced package-management system, but I've been fairly comfortable with the package-management system (as such) used by RHEL, and I'm inclined to stick closer to familiar forms. (It is not the quality of Red Hat's released code that has alienated me.) I think that my decision will be one between Fedora and Scientific Linux.

Fedora is the source from which RHEL is derived; Fedora is bleeding edge. Scientific Linux and CentOS aim to be very close derivatives of RHEL. Scientific Linux seems to be the most effectively maintained; unfortunately, when last I checked, the developers of CentOS hadn't got a stable clone of RHEL 6.0 out the door yet, and some of the changes from RHEL 5.6 to 6.0 have been meaningful improvements for me. (StarCom Linux, another close derivative of RHEL, lags even further behind.)

I downloaded a live CD of Fedora and a live DVD of Scientific Linux, so that I could try each. There seemed to be no non-trivial difference in either case from the look-and-feel of RHEL.

Anyway, the choice would seem to be one of functionality (Fedora) vs reliability (Scientific Linux).

[Up-Date (2011:05/23): On 11 May, I installed Fedora. I've had a few mishaps with fonts, and the system has been a little flakier, but so far the marginal benefits have seemed to out-weigh the marginal costs. I've also been giving some thought to installing a larger hard-drive, with one or more additional partitions, for other *nixes.]