First there was this:
You Can't Review Your Friends. You Just Can't over at AAR.
Then Jessica over at RRR posted a link to it and a lively discussion occurred in the comments.
And finally, Vacuous Minx posted A slightly different reviewing dilemma, also with an interesting comment section.
I don't have very much to add to the conversation, however, as a fairly new blogger, there are some interesting and important ethical questions here that I am glad are being asked. Reading the discussions on each blog, I find my own ideas of the kind of blogger I want to be solidifying. If you're a book blogger, I think it can be a really helpful group of posts to read. In fact, if you're a blogger you've probably already asked yourself these questions. And if you haven't well, it's high time you did.