I've recently begun following a blog/Twitter account that's too much fun not to share:
http://coverspy.tumblr.com
http://twitter.com/coverspy
It's comprised of a team of "undercover" New Yorkers (though it has since expanded to other cities around the world) who report anonymously on what the fellow denizens of their home cities are reading in public. It's a little like
Humans of New York, but even more anonymous; public readers are never approached by spies and usually don't know that they've been featured unless they happen to read the Tumblr or Twitter feeds and find that the short personal description accompanying the book cover matches them.
I've always been a bit of a Cover Spy. I tend to notice what my subway-riding compatriots are reading (and sometimes peer surreptitiously at the running headers on e-reader screens). Obviously, as someone in the publishing community, there is a natural inclination to pay attention to these things, but work aside, I find that it helps me keep a finger on the pulse of the city. There's usually a certain correlation between the books I see on the subway and bestseller lists or trending news topics. For example, there was a "summer of
John Green" on the F train at around the time
The Fault in Our Stars first hit theatres, and a spate of nonfiction about modern European history as the Euro crisis has been playing out.
But New York's cultural milieu is more than what's current or showing at the cinema. I often see people reading books you'd never expect at first glance; sometimes those are the most thought-provoking (teaches you not to judge a book by its cover, ha), like the guy in the power-suit reading Betty Friedan, or the little Jewish grandmother nose-deep in a science fiction paperback. I sometimes make up life stories for them in my head. I do.
Sometimes anonymity can be entertaining. Sometimes a title and author allow a moment of genuine insight. Until they catch you staring, and you have to awkwardly look away, or feign interest in something behind their heads.