Absolutely. Football is definitely king in America. I'd say one of the only places that isn't true is Atlanta (Braves I'd say are more popular than Falcons, and UGA Football reigns there). Obviously St. Louis. I'd say New York/Boston is a toss-up same with Philly. Although I'm not totally sure on that one.
Braves are marginally popular, really. They wouldn't be if they got bad. You're probably right, though. I wasn't even thinking of Atlanta. I would have named the same cities as you plus maybe Phoenix, where the Suns are fairly popular and the Cardinals pretty much lost everyone with their many years of suckitude.
New York is pretty even, Boston is a baseball town (maybe even somewhat of a hockey town), but Philly is definitely football-first. Don't be fooled by the Phillies' recent success, Phillies fans are truthfully not that loyal.