My best friend, with whom I travelled, has also been to the west coast, recently; this was his second time in NYC, and he said that San Francisco is now his favourite city - and in comparison to NYC, it gave him the impression he was seeing 'America'. 'New York' is a concept within itself.

He also noted that Times Square was similar to Las Vegas; there really isn't very much to 'do' there other than 'doing nothing': seeing, looking, becoming overawed by your own awe, experiencing your own experience. It also comes alive at night.

(More on hyperreality here. Read Baudrillard in particular, and his essay on Disneyland.)

I never visited London before our smoking ban. In all enclosed public places, smoking is now illegal in the UK. As for the air in general, it's difficult to make a comparison: NYC was so humid when I was there, very stifling, though to me personally never overwhelmingly so. I think London is less naturally humid, but more crammed with people. It's a busier city, somehow; and physically, less navigable, less simple in its structure; no grid system, more chaos. London is sprawling.

I should also note that, in central Manhattan, the streets are very clean. There must be a lot of waste, but to where it goes is unknown; the streets themselves are spotless. Or it might be a case of the architecture making you look up more than you look down; I could have been stepping in anything.