It's too bad the Seraph went down...we had an awesome "How to not piss off the mods" thread (started by VHawk

). It didn't help stop the madness, but it was so fun writing it.
Luckily here we don't have as many 8 - 10 year olds with no sense of grammatical literacy, so the spelling/caps/run-on sentence problems aren't as bad.
Misspelling the word definitely (just think of "finite") is the absolute worst.
Wrong forum is just exponentially increasing. I really don't remember it being this bad last year, but since I was a newb here I probably wasn't paying attention. I've drawn my line in the sand on that one.
Other than things already stated, I'd go with blatant annoying homerism posts that don't really help anyone determine if a player is good or not. I like to hear that a player is impressing members from a neutral point of view. More often than not the post turns into a "fighting words" war anyway.