Ad for a New York radio station on NYC subways.
HMDT, New York?
All I've ever heard in NY is how Red Sox/Yankees is not considered a rivalry in New York. That said, the ads on the MTA are probably not indicative of anything.
As a Mets fan born in Astoria, I can tell you that this is the breakdown of baseball fans in NYC: 1/3 Yankees, 1/3 Mets, 1/3 don't care/some other team. That 1/3 Yankee fans is currently preoccupied with the Angels, Tigers, Rangers and anyone else who's gotten the better of them in the playoffs over the past few years. If my Mets were competitive, I'm pretty sure the Yankee fan's second target would be them -- though interleague play days still make us Public Enemy No. 1.
Then it's the Red Sox, but you have to take the temperature here. The Yanks haven't played the Sox in the playoffs in almost eight years. The idiot Yankee fans here think the rivalry's over because "they" won the WS in 2009 and, thus, have the most recent title to their credit. Plus most Yankees fans are Giants fans and seem to think the Giants' success against the Pats in the Super Bowl diminishes makes NY teams better than all Boston squads.
There are more Sox bars in the city than there were in 2004, thanks to the Riviera, Professor Thom's and the Hairy Monk, but the "rivalry" is pretty much nonexistent down there. That MTA sign doesn't indicate much other than that the MTA needs to stop hiring Bergen County kids fresh out of Drew University (a place that makes Bridgewater State look like Oxford) for its marketing/PSA team.