I live close to nyc so I visit there quite often, but suprisingly you wont see too many hardcore fixed gear riding messengers. NYC is filled with just average commuters on their beat up mountain bike. I do see alot of fixed gear bikes locked throughout the city, and if you get near a bike store(Within .5 mile radius,) there just seems to be more and more fg bikes. I have yet to go to Boston and check out bikes there though, I know there is ALOT of fgss riders in Boston however!