This is a little off topic, but I've been meaning to mention it for awhile.
From my limited experience, I've found the opposite. Most of my friends who grew up in Providence have STAYED elsewhere after college (with the vast majority in New York and a few in Boston). I wish I could report otherwise, but that's the reality. Granted I grew up on the East Side and went to overly-expensive private school, so people had the mobility to leave...not many of us have come back voluntarily. Many of my friends claim they want to return "some day" but they'd rather spend these years in places like New York, LA or San Fran. I'm not going to argue that little PVD can ever compete with those places, but I think it's worth a discussion.