Sam Bauers announced on the bbPress developers blog that release candidate 1 has been pushed out the door. According to the post, progression towards 1.0 will increase with these release candidates. Despite this version being a release candidate, Sam does not recommend using this on a live website just yet. If you want to see what’s changed, he recommends performing a fresh install.
If you find any bugs in RC1, submit them to trac so Sam can take care of them ASAP.