Seems like things are starting to move forward, based on an announcement made in the bbPress.org forum today:
Hi everyone, bbPress 1.0 is moving beyond Alpha stage and skipping Beta to go straight into a series of Release Candidates towards a final 1.0 release. The first RC is now available for download.
We’ve made this decision to push towards 1.0 final as the scope of what was going to be included in 1.0 has been whittled back and we have had some serious real world trials through TalkPress.
I’ve been playing with bbPress for the still-in-progress URLuscious.com, so plan to try out the new upgrade in the next few days and will keep you posted when I have a live version available for folks to check out.