I've covered this before, but, to anyone who is on the Mac beta channel but would prefer to be on the stable channel, now (i.e. before 4.3 Beta 1 is released) is your opportunity. I covered this back in November, but when we ship an RC to the beta channel, if you have previously set your update channel to beta, and you'd like to go back to stable, you should type "set update channel to default" in the command bar.
http://community.logos.com/forums/t/26388.aspx