This is so wrong, and will likely make a lot of people much more reluctant to trust online reviews. In the end, authors will suffer. As an author, I would NEVER pay for a favourable review. EVER.

‘Suddenly it hit him. Instead of trying to cajole others to review a client’s work, why not cut out the middleman and write the review himself? Then it would say exactly what the client wanted — that it was a terrific book. A shattering novel. A classic memoir. Will change your life. Lyrical and gripping, Stunning and compelling. Or words to that effect.’

via Book Reviewers for Hire Meet a Demand for Online Raves – NYTimes.com.