I dunno, probably not too many, It was before he did Assassin's Creed, I was pretty early to the party, I actually kinda followed Yahtzee here from FullyRamblomatic.com although I discovered that after ZP was created.
I saw the Fable review on youtube, went to fully ramblomatic, saw that he was here now and then watched the ZP episodes that existed and spent the next ages going through the archives over there.
Now I'm finding myself spending less time here and shifting over to Destructoid slowly due to Jim's show (Jimquisition, obviously) after listening to Podtoid from the first available downloads on iTunes.
I tend to drift around a fair bit, although I've been here quite a while.
EDIT: It's funny how many other people only joined the forums after being here a while.
IIRC I lurked for a few months, not very long at all; but for the longest time I didn't even know there were forums on here. Probably a solid year and a half.