Theresa and I both have generations of family history in Chicago, and I expect we both are quite familiar with the "youse guys" Chicago accent. Probably everyone is familiar with a bit of it because of all those SNL skits about the super "Da Bears" fans.
I've always so much associated this with Chicago area, I was quite surprised to hear a very similar accent in Cleveland and Buffalo. It's a Great Lakes accent, really, though I don't think those on the north side of the lakes (Canadians) have much of the accent. To some extent, it crosses the class barrier (that is, a banker might sound that way, as well as a steelworker), but not the race barrier (African-Americans and Hispanics, even those with generations in the region, tend not to have those distinctive vowels). The further you get from the Great Lakes cities, the less you'll hear it. I live 100 miles south of Lake Michigan, and no one around here sounds like that-- we Hoosiers are more likely to flatten out vowels than shift them.
Anyway, here's an article about the Northern Cities Shift ("NCS") or Great Lakes accent which points out the funniest aspect (apart from "youse," which I can tell you from my own experience is actually the possessive pronoun used by the purest speakers) is: If news of this radical linguistic shift hasn’t made it to you yet, you are not alone. Even people who speak this way remain mostly unaware of it. Dennis Preston, a professor of perceptual linguistics at Oklahoma State University—he doesn’t merely study how people speak, he studies how people perceive both their own speech and the speech of others—discovered something peculiar about NCS speakers when he was teaching at Michigan State University. “They don’t perceive their dialect at all,” he says. “The awareness of the NCS in NCS territory is zero.”
Point is, while we tend to mourn the loss of American dialects due to mobility and TV, this accent is actually become MORE distinctive. Interesting!