The Mozilla development team quietly announced the release of Firefox 3 release candidate 1 over the weekend.
The announcement was posted on May 18 and indicates that RC1 is a "public preview release" intended for testing and feedback. RC1, which was expected to be released by the end of May, is the final testing step before Firefox 3 is formally released to the public. Mozilla said the Rc1 was code complete on May 11 but it needed cleanup before widspread testing would be possible.
The Mozilla team has not specified a final ship date for Firefox 3 but sources in the linux distribution community say they were promised final copies in June.