It looks like a couple of contributors to the upcoming book "Many Worlds? Everett, Quantum Theory and Reality" have uploaded the chapters the wrote onto arXiv. I'm not complaining since it makes for a good bedtime reading!
I mentioned earlier the essay by Adrian Kent that I would say was critical of the Many Worlds interpretation. Now along comes Max Tegmark's article that will appear in the same book.
Abstract: Everett's Many-Worlds Interpretation of quantum mechanics is discussed in the context of other physics disputes and other proposed kinds of parallel universes. We find that only a small fraction of the usual objections to Everett's theory are specific to quantum mechanics, and that all of the most controversial issues crop up also in settings that have nothing to do with quantum mechanics.
What is fun about this essay is that he reveals a "poll" he did at the Perimeter Institute on several questions regarding Many Worlds and interpretation of QM.
Boy do I have a lot of reading to do over the weekend! :)