Ok the question is in each of the categories above, what do you tend to favor the RTM, RC, Beta, Alpha, Pre-Alpha, etc

For OS and service packs I go with RTM only. I really dont like beta testing that stuff.

For drivers I use stable release, except for NVIDIA GeForce drivers. Those I generally use betas.

For applications, its a mixed bag. For example I only use Firefox releases but I have no problem with Ad Muncher betas or the latest SMPlayer builds.

Hell I use anything if it promises to be faster/better

Unless you are an official beta tester, I've never understood installing the beta version of anything.