Fixed that bug, NB is now showing who's online. About the thread bump feature.. we don't recall having that, can you elaborate? You can bump threads by replying, but replying just to bump is actually not a desirable behavior.
EDIT: And yeah, Will changed to horizontal postbit. I think this works better too. Postbit is a little high in some places, but the space saving on posts seems to more than make up for it.