Leafra
I hate it when people just post an OOC and not post for the RP. I do it too sometimes its when people do it all the time that drives me insane.
I also hate it when people say that your RPing wrong. This has happened to me once. This person PMed me saying that he quit the RP because of my grammar and because I did not spread my post out. It hurt my feeling really bad. I am still not a good speller and I have gotten better with my posts. It has not happen again but when other people tell others that they are RPing wrong makes me kind of mad.
Also when people post in a thread not even related to the topic. Its kind of rude and annoying.
Also being mean to noobs. We were all noobs at one time so I say give them a break.
Thats all I can think of right now.
That guy sounds like a jerk, but it was his loss. =)
Those sound like reasonable pet peeves though. My brother's a noob, he's trying to learn now, I think its kinda cute in a funny way... but I wont roleplay with him... >.> lol.