This preview makes me really excited for the 4.2 release!
One suggestion however: for the "Add Moderator Message" function (~45 secs. into the video), I think it might be best to highlight or otherwise distinguish the Moderator's message - otherwise it may get mistaken for another forums post for people who may just click the Forum topic heading, then use their mouse wheel to zip down to the most recent post (of which there are many, I imagine).
So maybe use icons for the Moderator message similar to what you do for the Recommend option? Or the existing Post Highlight? Something to make it stand out a bit more so people don't miss it?
