Yeah Play By Post (PBP) wouldn't work, but I think that's a self-solving problem. Any gamer would only have to go through about a half hour of:
"I rolled a 12."
"I like Mutants and Masterminds, but not its so-called 'magic system'."
"I use House Rule X."
"I play a half-orc with a third eye."
"You hit the dragon. Roll damage."
"GURPS is da bomb, yo."
"GURPS is for slack-headed freaks. D&D roolz."
"Shadowrun. IJS."
"I got it for six hit points."
"GM tips anyone?"
"Dude, I said roll for damage."
"Anyone play Tunnels & Trolls?"
"I did, I hit it for six."
"Star Wars RPG: Sucks or not?"
"Let's go to another board."