I have been an avid reader pretty much since I could read. I remember when I was little there were whole summers that I spent inside reading book after book. I would even get annoyed when the neighborhood kids tried to get me to play outside. In college I was not allowed to read during the semester, my classes would have been totally neglected. These days when I get really into a book, I've been known to stay up really late (into the wee small hours of the morning, generally not past 2). It's nice to be able to read when there isn't anything else I'm supposed to be doing (other than sleep but I can talk myself out of that by saying I don't feel tired).
I've noticed that the books I read kind of go in shifts. For a while I was reading a lot of British chick lit. At another time, I kept reading books about women who got out of bad marriages and had adventures. Once I even had a system where I would read a modern book, then an old/classic book followed by nonfiction and back again. Lately, I've been reading mysteries almost exclusively.
What I love about books is the ability to be in another world and leave mine for a while. Then, once I'm hooked, I have to know what happens next. I've even been known to finish a book I didn't really like all that much just to find out what happens.