"So, if a review is not meant for the writer of the book, then who?
Other readers, of course! (You knew that already, you are so smart.) Potential readers can see if the book sounds like something they might like. Those who have already read the book can use the review to open up a discussion, discover nuances they missed, and so on. A review can turn the intimate experience of reading into a conversation that enlightens both sides."Robin Brande has two great posts up on writing...here and here.
Ally Carter's posts on writing YA were amazing. The Wrong Questions. The Questions That Aren't Getting Asked At All.
I've stumbled upon these mock newbery sites. Anderson's Bookshop. ACPL Mock Newbery. Anokaberry (and here). Eva Perry Mock Newbery Club, Glendale Mock Discussions,