You used to be able to track the build process for CentOS when it was a RHEL clone, see how many packages were left to go as the days crawled past.
Things are a little better with the way that development happens more recently. 6 was a massive delay for distributions because RedHat had overhauled a lot around the build process and distributions needed to completely overhaul their stuff too, in ways that weren't that obvious.
Just wanted to clarify, I agree with you completely. I didn't anywhere perpetuate the unfair "it's just produce rebranded RPMs" (which is actually accurate, but trivializes the significant process involved in rebranding and rebuilding, hence IMO misleading). It's a significant amount of work. The time it takes is not unreasonable given the effort involved. That said, the amount of time was painful. I've never complained about it because I'm grateful for anything and everything they do, and I'm not complaining about it now. I'm recognizing the facts around speed of delivery, but in no way suggesting they aren't for a good reason.
Most of the time I think it's fine. Mainly it hurts when there are security updates you need.