Absolutely NOT the coolest neighborhood in Chicago, although aarestad is right about the rest. I can think of about five neighborhoods of equal diversity that a random sample of miscellaneous Chicago residents would probably consider more 'cool', although there are some noteworthy places worth checking out in Rogers Park.
The Heartland Cafe has great food and often supports good bands. Exit Cafe is a much teenier spot down the street from the Heartland where smaller, more beatnik-like bands perform and there are always interesting people sitting around with whom one can play checkers, cards or penta.
The Morseland is kind of nifty; its like a club but smaller, like a bar but darker and louder, and where my friend DJ's each Sunday.
Loyola University is in Rogers Park, lending to a large amount of college-age people and the usual coffee houses and shops that accompany them. One amazing thing about Rogers Park is the fact that, despite the gentrification that has started there, one can still find a good-sized apartment for very cheap rent.