I've been a bookworm since I learned to read. For me, most books fall into two categories: read once and donate to the library, or keep and re-read. There's a third category that one of my friends calls "life is too short" for books I don't finish, but that's a small category. (Ann Boleyn was a vampire? Really?) Prior to the advent of self-publishing and free Kindle books, it was even smaller.
When I moved cross-country in 1979, I sent 49 boxes, 25 of which contained books. I still have most of them. Some are fragile paperbacks kept in a media cabinet away from sunlight, and some are hardcovers kept in a set of barrister's bookcases.
As eBooks became more readily available, I started to shift over to them. I got a Palm PDA to serve as an eReader and replaced it twice as the devices wore out. Then I got a Kindle, a third-generation Kindle when my first one wore out, and an iPod with the Kindle app, which is great for reading in bed (no more having to sneak a flashlight under the covers).
At the moment I'm reading Love on the Run, by Katharine Kerr, which just came out today. I'm also re-reading A Civil Campaign, by Lois McMaster Bujold (I'm going through the Vorkosigan books again) and I've just finished reading Elfhome, which came out at the beginning of July, for at least the fourth time. It's the third book in a series by Wen Spencer, and I just discovered that she has two short stories set in the same world available for Kindle: Blue Sky, which I've read, and Wyvern, which I'm about to.
One advantage to eBooks is that they don't take up shelf space. They also don't have to be dusted, and they don't get damaged. As long as the company you bought them from stays in business, you can retrieve them years later; lately I've been logging into my account at Baen and clicking "Email book to my Kindle."