I just moved to NYC from Los Angeles. Been here for a few weeks.
Initial impressions: the subway system is pretty cool, and it feels like a "real" city, unlike Los Angeles, which is pretty spread out. I like the fact that I don't have to drive. And there are a lot of good restaurants here, although I think L.A. definitely has better sushi and mexican food.
Two things that really bother me though about NYC are the weather and women. I could deal with the former, although it will take time to adjust. But I've been utterly shocked at the low quality of women. Just this past weekend, I went out to a bunch of spots, like rose bar, 1OAK, beatrice inn, bungalow 8, and a few other places. The entire weekend, I saw maybe 2 or 3 girls who were hot. And even they would be barely above average in Los Angeles. Jut walking around the city, I barely see any eye candy.
Don't get me wrong. NYC is a great city with lots to offer. But hot girls is not one of them. For that, you gotta be in Los Angeles, San Diego, Miami, or Dallas.