Times Square is probably only rivaled by whatever the central area of Tokyo has for crowds and raw spectacle (Vegas doesn't count--they're just doing for show). That said, unless you have a strange fetish for being in chaotic masses of people, I'd stay away between 7-8pm and 10-11:30pm. The shows really make getting around and even really seeing what's going on pretty hard (even by yourself). More seriously, the cops on horseback that are ever-present during those hours make me nervous.
Pros: Unique, Visually amazing, Many stores
Cons: Cops on horses, Rush crowds
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