I’ve Just heard and participated Reviewback, a blog review exchanging service.

Simple!, you submit your blog into the site and then browse over the entire network and find other bloggers to trade reviews. You can browse the blogger sort by Name, Age, Google pagerank, Alexa rating and tags. To make it easy, you also can choose from blog categories to find bloggers with similar interests.

For me, this service is good for bloggers to receive backlinks from other blog. With this free service, you can gain more exposure for your blog, increase your blog pagerank, ratings and visibility. Register Reviewback.