I have yet to play one, single game of LoL that didn't involve some five-star bitching and asshole-ism.
Hell, I remember one game when I played fairly well, but in a way that was a little unusual for my champion. No sooner than the "VICTORY" screen pops up, a teammate slams me for being "the worst goddamn player he has ever fucking seen, for playing wrong," and the level 2 guy that was trying out a free champ for "being some know-nothing asshole that can't play for shit, seriously, just go die in a hole." Oddly enough, I actually did better than he had, so I guess he was just upset.
But yeah... When LoL works (read: you have a team of friends to play with), it really works. When LoL doesn't work, you have a mediocre game with a generally abhorrent community.