This is the deal, and I'm not too sure I support the idea. I leave it up to you - Here's their pitch on their website http://www.harpercollins.com/Members/FirstLook/index.aspx
Join the HarperCollins First Look program to preview books in literary fiction, general fiction, suspense, biography, cookbooks, and other genres, for readers who make a difference – like you!
Each month, Advance Reading Editions (AREs) of great books by fabulous authors are offered that you will have the opportunity to review. Reviewers are selected at random, but you must register to be eligible. In joining the program you may select your favorite genres and we will let you know when a book in your preferred category is offered.