This one is called Page 99. http://page99test.com/# This one differs from a site like Webook.com in that the writing posted there is from page 99 of a book, not pages from the beginning of a book. The site explains to writers that page 99 in a published book is approximately page 150 in a manuscript properly formatted. The writing can also be from published writers.
I spent some time on the site yesterday, its first day. One complaint I have is that when writers copy/paste their work, the site whacks out their formats. Hopefully they will fix that soon. Also, like Webook.com, Page 99 lacks an historical fiction category. Such writers have to lump their stuff in with general or literary fiction. As a reader of historical fiction, I’d much prefer to read specifically that and would be able to give more pertinent opinions when it comes to the part where you are asked if you’d buy the book. I’m never going to say I’d buy a book if it’s in a genre I don’t read, such as most contemporary stuff.
Page 99 does allow readers to leave comments, unlike PageToFame on Webook.com, which of course is always a double-edged sword. 😉 The other things left by the reader is if they would turn the book’s page after reading page 99 and how likely they are to buy such a book.
Actually I think the site offers more value to published writers. Free advertising, so to speak. Post page 99 from your book and when the results of the reader’s “vote” pops up, they can see that it’s a published book and see the author’s name and the book’s title. Then it’s just a click away to Amazon.com and you can buy the book. In fact, Page 99 might consider adding just such a link for published works.
When it comes to value for unpublished writers, I suppose the value is being able to get feedback. However, the value of such feedback from one page in the middle of a book remains to be seen.