The next milestone for the development of Windows 7 is the Release Candidate or “RC”. Historically the Release Candidate has signaled “we’re pretty close and we want people to start testing the release, especially because all the features are done.” As we have said before, with Windows 7 we chose a slightly different approach which we were clear up front about and are all now experiencing together and out in the open. The Pre-Beta from the PDC was a release where we said it was substantially API complete and even for the areas that were not in the release we detailed the APIs and experience in the sessions at the PDC. At that time we announced that the Beta test in early 2009 would be both API and feature complete, widely available, and would be the only Beta test. We continued this dialog with our hardware partners at WinHEC. We also said that many ecosystem partners including PC makers, software vendors, hardware makers will, as has been the case, continue to receive interim builds on a regular basis. This is where we stand today. We’ve released the feature complete Beta and have made it available broadly around the world (though we know folks have requested even more languages).
I read the first few paragraphs and then got bored!
I think it could be summarised as "The beta we just released is complete but we're still testing and fixing stuff and adding drivers... There won't be another beta because this one appears to work quite well. There will be a release candidate (but that's not a beta - it's a release candidate) and then we'll release the finished product (except there's no such thing as finished software)."