Thanks to those that responded over the last few weeks. I ended up writing a blog post about my findings, since I had to do so much digging that it seemed like I might as well summarize them in the hopes of helping others. The chart I posted organizes my findings:
One caveat, which I touched on in the blog post, is that the chart is useful for checking the capabilities, but the real advantages to most frameworks are their unique features. I chose Moq in the end because of the easy to use API. Also, all the information is subject to errors and change – if you disagree with something on the chart, please post a comment.