Release Candidate 2 of Firefox 3.0 has appeared on Mozilla's FTP servers. You'll recall that last week, Mozilla decided that it needed a second RC in order to address bugs found in the RC1 build.
The download links at Mozilla's site have not been updated, but this is the right place for the build to appear, so this is the real deal.
The download site has not been updated, and (naturally) release notes are not available, but I'm downloading anyway.
Oh, and extension makers: I hope you're watching. I expect (hope?) all my favorite extensions to be working when FF3 goes final.
Update: Download site has been updated; release notes are here.