First, an aphorism that I think it worthwhile to carry around with you (found in no less worthy a place than Gmail's advertising ticker): from St. Augustine, who was named for Tully's daughter: "Patience is the companion of wisdom." So, maybe you're not all that wise, at least you can act like you are.
And an opinion of Mark Liberman that should probably be printed on all the world's currencies --and flags: "But I also believe that it's also morally wrong to try to win an argument by making fun of non-standard speech and lack of formal linguistic polish." (Read more about Liberman's views here. It's about Sarah Palin.)
I can't judge why it would be morally wrong, since I haven't yet encountered an intellectually satisfying moral system, but I can see (now that I think about it) how it's logically wrong --it's an ad hominem attack. In other words, a person's accent has no bearing at all on the content of their argument. The only thing you prove by making fun of accents is that you are a provincial snob.
What I find so remarkable about this is that EVERYBODY IN THE WORLD DOES IT. Lynne Truss's fame is entirely based on it (I think. She wrote Eats, Shoots and Leaves, which I haven't read but I think it calls for fatwa against people who misuse apostrophe's). So, let's all be better than everybody in the world and stop thinking that regional accents make people dumb. Sarracuda has lots more going for her in that area.