The other big addition has been one bookcase solely devoted to my young adult collection. This, of course, being important since I review YA SF/fantasy professionally. However, this still leaves me with a quandry: Do I take up valuable space there with the Harry Potters, or stuff them in one of the miscellaneous shelves I have elsewhere? Ditto the Oz series. It's all the little details that drive me neurotic. I play favorites, see. L. Frank Baum gets slapped together, ditto Diana Wynne Jones (or does she? Right now, split between YA, trade paperbacks, and paperbacks) (that's right, due to limited space, I can and will sort books by size/type to make maximum use of shelf room....)
I'm just thinking out loud. I'm at my happiest when surrounded by books, and I like moving them around every so often anyway. :)
So how do YOU folks organize your libraries?