I came across an interesting article on Techcrunch.com regarding ebook subscription services, and why the various companies offering them may have a tough road ahead:
The article also does a nice job of comparing and analyzing the subscriptions offered by Scribd, Oyster, eReatah and Amazon.
I did a little bit of browsing of each, and wasn't particularly impressed with any of them. eReatah seemed like it might offer the largest selection of books, but I'm not sure that $14.99 per month is cost effective. Especially when $14.99 only allows for 2 books per month. But, I guess it really depends on your individual needs. Regardless, I'm still intrigued by the concept. If a company comes along that offers a wide variety of selections and is cost effective, I might be tempted to give it a shot.