You know how sometimes you recognize a change only after it's happened? And then you say, wow, when did that happen?
I feel sort of like that. I was looking for some stuff in my home office last night, and I looked at some of my books, and thought, I haven't read that in years, and I have no urge to read it. Maybe I'll take it to the free shelf at school? (We don't have a good used bookstore in the area, and these are outdated lit crit/theory sorts of books that I don't think would have enough resale value to make it worth loading them up and taking them to a bigger city.)
It's not that I don't buy books still, but I have far less of an urge to keep books I don't find useful. Some books I find endlessly useful, even though they're as old as these that I don't find useful. In grad school and for a long time thereafter, having the books was really important to me. Now, maybe not all of them are.
I'm going to take a few of them into the free shelf every month or so. Or not. If it feels good after a couple of trips, then sure, I will. If it doesn't, then I won't.
But really, do I need several books by Jane Gallop? I haven't read them in years, and I think I can live without them.