Many people are into writing reviews for backlinks these days, thanks to the trend started by John Chow. Here are some opportunities that may be of interest to you fellow bloggers:
http://shawn.ocia.net/ (also with top commentators list)
http://garryconn.com/ (see http://garryconn.com/who-wants-to-exchange-links-with-me.php ; also with top commentators, called “top contributors”; you may sponsor one of his Successful Blogging Tips posts by writing a post about his blog)
http://www.linkrain.com/articles/review-my-blog-to-win-a-50-cash-prize-and-get-a-pr4-backlink/ (review contest; more opps available on the Advertise page; displays top commentators)
http://www.alltipsandtricks.com/ (has a rolling blogroll series – see http://www.alltipsandtricks.com/blog/2007/02/13/review-me-review-you-the-rolling-blogroll-has-launched/ ; top commenters available)
http://www.jonwaraas.com/ (see http://www.jonwaraas.com/review-my-blog-get-a-free-backlink-and-review/ ; also has top commentators; beware, his current blog header may look a bit embarrassing for the shy ones)
Please note that I cannot guarantee your favours will be returned by the owners of all those blogs. If you have any doubts, contact them all first.