This actually caught me as a big surprise. For weeks I had been assuming that Vista would be pushed back even further and that we wouldn't see a release candidate build for a long time. However tonight, according to the Windows Vista Team Blog, Windows Vista RC1 is complete and available for download by TechBeta or TAP participants.
More applicable to me, but right alongside the Vista release is the announcement of the .NET Framework 3.0 Release Candidate. This is available for anyone to download via the link above. The SDK is also up for download. I know this isn't right on schedule, but I'm impressed that Microsoft brought everything together. Now they just need to get the tools closer to being ready.