So, I live in NYC, don't have a car and use public transportation or walking to get everywhere. Lately, on the trains, more than the buses, so many people have e-readers. I used to look at people's book covers for adds to be to my "to be read" list or just to see who was reading what. It's always interesting to see people's reading material. You see the students studying or scribbling assignments to be turned in; people reading the NY Times (in rush hour), or their religious texts, or romance novels (very popular amongst every race and age group of women), or bestsellers. If I saw more than five people reading a book, I would generally try to borrow it from the library or buy it. Most of the times the books were actually good books. Some were demonstrations of the power of a good publicity department.
Now, lots of people have e-readers. There is really no way to politely find out what someone is reading and many people don't like talking to strangers on the train, hence the nook or the Kindle. Subway book spotting was an easy way to get an idea of what was hot and what wasn't in the book world. I'm too shy/cautious to ask someone what they are reading. I have had people tell me they were reading the same book in their e-reader.
Would you ask a random stranger with an e-reader what they were reading?