> In the Unites States, That is denser than just about any place other than Manhattan.

I think that depends on your definition of "just about." Every borough in NYC aside from Staten Island is much denser than San Francisco. Additionally, many parts of where I'm from – northern NJ – are even more so: Hoboken, West New York, Union City (the densest city in the country), Guttenberg (the densest township in the country), and more.

If you're talking about cities larger than a certain size, then perhaps, but even then, I personally think it's a bit misleading to single out just Manhattan.