It's Red Hat that it's not including stuff in RHEL, not that CentOS is slow tracking features. So you get the same stuff with Scientific Linux (mostly, both SL and CentOS package some extra bits, but overall is RHEL).
It's API/ABI stability, and it's meant to be a feature of RHEL.
It's API/ABI stability, and it's meant to be a feature of RHEL.