I don't mind accents very much, but I have a serious problem when people overdue them, which I've seen a lot of lately.  If your from the other side of the known world and don't understand a person, thats one thing.  But you could easily have a character from the same region as theirs who would have no trouble understanding their accent.  Giving your characters inane, incomprehensible accents just limits other peoples RP in ways that you shouldn't have any control over how they are limited.

Ugh, those accents are the worst. You know your accent is too strong when it takes players five minutes to respond to your says. Please, for the love of god, tone it down and be comprehensible!