I liked what Susan had to say yesterday, and I echo her sentiments and will add a bit to them.
There's a lot more pressure now to read for 'business' purposes--for education, or to keep current with the culture, or research, or out of obligation to fellow writers. Not that those books can't be terrific, but they're chosen for reasons other than absolute interest.
For the most part, though, I still read for the same reasons I did as a child--to be astonished and delighted.
I don't read many craft books anymore--I'll periodically reread King's On Writing, or Goldman's Adventures in the Screen Trade, but my rule of thumb is that a book on writing has to be well-written; if I'm bored reading it, I'm skeptical of the advice it contains.
I think a lot of literary culture--and I'm speaking mostly about what I've seen in Canada--revolves around books that people think they should enjoy. There are certain prizes that go to the kind of books you could imagine on the shelves of The Right People. To me, those are the books I'm least interested in. I think that's what turns people off reading--they think once they're out of their teens that they should be reading Big Important Works by Big Important Authors, instead of reading fiction, or fantasy, or comics, or crime novels, or children's books, or whatever they truly enjoy.
So there's more consideration put into what I read, but I still try to spend most of my reading time on books I'm passionate about.