"Down-to-earth and full of life"
Below 96th Street, Amsterdam is a great avenue that embodies the eclectic artistic nature of the Upper West Side. On weekends, you'll find crowds lining the sidewalks (even in the winter) for the best Sunday brunches in New York City; on weekdays, the streets are populated with shoppers visiting the many cute stores and restaurants in the area. At the south end of Amsterdam where it intersects with Broadway, it's a bit more upscale, but the northern parts are still great. They're just very down-to-earth and homey - a very different vibe from their classy/chic southern counterparts. There is plenty of nightlife on Amsterdam, particularly in the 80s where cheap college bars abound. If I had to compare Amsterdam to something on the east side, I'd say it most resembles Second Ave: a nice mix of residences, stores, bars, and restaurants, without being too pretentious.