I love a good long browse too but browse less these days because of the temptation to actually buy books and read them at home. Re the Guardian article, I've been to 3 of those stores: Strand (I'll go back when I'm in NY next month), Shakespeare & Co. (a purportedly American literary bookstore that [shock!] didn't have WC Williams' Collected Poems) (it has been said that there's a superior English-language bookstore elsewhere in Paris), and City Lights, a disappointment, a tourist trap. As compensation, not far away, there's a very good second-hand bookstore in mid-Berkeley, don't recall the name.
New Yorkers - are any bookstores that specialize in poetry trucked away somewhere in some of the boroughs? How about second-hand bookstores that have a lot of good old noir / hard-boiled / golden-age sf paperbacks?