Oyster is an all-you-can-read ebook subscription program. Commonly described as Netflix-for-Books. Officially it was opened up in September,
but it is still in a private testing phase. I signed up and have used it for the last three weeks.
My overall impression is fairly positive. When you sign up you are asked to choose five books from your computer browser. These five books will be in your account to get started. The main problem is that on the computer, there is not a search function. So you have to look through book covers sorted into categories. These are their most popular books, so you should not have too much problem finding books you are interested it.
Once you complete the registration process (pretty basic) and give your credit card information ($9.95 a month but with a free one month trial) you are emailed a link for the iPhone app (you can just find it in the app store as well). Once you sign into the app on your iPhone, you can search for books, load the books that you chose on your computer, and update your profile (connect to Facebook or Twitter, search for friends that are on Oyster, list your favorite books, add a picture and write a bio).
Oyster has a good selection of books, they claim 100,000 books, but Smashwords has also said that their entire 250,000 book catalogue of independent authors will be added soon. I was able to find CS Lewis, Ursula Le Guin, NT Wright, Margaret Atwood, Susan Howatch and a lot of other books that I actually want to read.