Doc Entropy's take is exactly right.  All I'd add is that on their native soil, they're tolerable, even a little likeable.

Catch them away from the city and they're defensive-aggressive, as though working hard to live up to some internal image of big, bad New York.  Its too bad more of them don't strive to emulate the Algonquin Circle group, rather than the Yankee Stadium bleachers.

  These were an impressive bunch back in the city's heyday (roughly 1900-1965).  As the nation's cultural, intellectual and economic/financial capital, and the center of its greatest architecture and museums, NYC was the city of the 20th Century.  Even in its decline, the city acquired an aura of danger and excitement it had previously lacked; NYC in the 70s and 80s was a lousy place to live, but a great place to be an artist.  Now that even its financial dominance is in question, NYC is being turned into a playground city for the rich and a tourist city for the middle-class.  While there are still New York snobs out there, they are an increasingly pathetic bunch, who don't seem to realize how their city has declined as a national center of thought, culture and enterprise-even if its quality of life (for those who can afford to live there) is higher than ever.