Yanks/Giants/Knicks here. Couldn't give a damn about hockey, but if I had to pick it would be Rangers I guess.
I always thought the Yanks/Giants and Mets/Jets thing was both a class and regional thing, in addition to having albeit less to do with a mutual stadium.
Yanks/Giants were a LITTLE more upscale and generally from Manhattan, Bronx, Staten island, Jersey, Westchester.
Jets/Mets out of the Dodger tradition of being a BIT more blue collar and Brooklyn, Queens, Long Island based.
Both my grandfathers were decidedly blue collar and split evenly Yanks/Giants (Manhattan born) and Mets(Dodgers)/Jets (outta Brooklyn.) The first one took me to the games, though, so I have been in that camp for decades. Too many decades.
Anyway, all this started to water down when Giants moved to Jersey.
That's my two cents.
I'll try to take some pics at the PARADE.
Fuck Bill Belichick and especially Rodney Harrison. And a perpetual FU to the Sox fans.