I suppose it is not a sign of my good taste or reverence for books that so many I own are paperbacks. I have fairly strict criteria for buying hardbound volumes: If the book is a gift, if it is a work I expect to frequently reread, if it is a reference book, or if it is something I just can't wait to get my hands on. (Also, if it is offered at steep discount from Sam's Club or Costco, but I can be flexible on that point.)
Thus, I recently sent my brother, for his birthday, a hardbound copy of Ian Rankin's new title, "The Naming of the Dead" even though I'd have been content to wait for the paperback myself. That's not an entirely selfless act: While I have loved nearly all the Rebus novels, I've found the most recent entries to have taken on kind of a meandering quality. I'll see what my brother Mike has to say before picking up a copy for myself.
A number of books in my eclectic collection of hardbounds I'm not particularly proud to display -- there are quite a few Stephen King titles, for example, bought years ago when I really wanted a page-turner for a long trip or something. In my defense, all were steeply discounted.