That prediction said that iMacs would be announced at MWSF, which as you know was six weeks ago.
Yea that's not the most trustable source of information. It'll be before the end of Q1.
If Apple is going to release Clarksfield or Arrandale based iMacs before the end of this year, they're going to have to get on a faster development cycle than they seem to be at present.
I just mentioned something, I don't really care about update after the next models because I'm going for one of those. Apple always comes up with something cool