Work has standardise on RHEL/Centos with a policy of updating quickly.
One thing I found that compared to Debian there are a lot of packages missing. Fairly common things like collectd, nginx and memcached are the ones I particularly miss.
There are 3rd party package sites but these seem to be a bit random in quality (but at least enough people run it that 3rd party packages are common) and obviously you can still have problems. For example the recent 5.5 update pushed libevent from 1.1 to 1.4 (well overdue I suspect) but the 3rd party rpms I use for memcached depend on libevent 1.1. I'll probably end up rolling by own rpms but having packages directly supported in the distributing is good.
I have to find out a package/version list for what is in 6 to see if some of the missing ones above are included.