Not to hijack the thread too much (I'm also very curious about the answer -- I'm one of the Review Board founders and these discussions always interest me), but

Not to hijack the thread too much (I'm also very curious about the answer -- I'm one of the Review Board founders and these discussions always interest me), but we support TFS these days in Review Board by way of our Power Pack add-on product, if you'd like an alternative solution. I can talk to you more about this off this thread if it's at all interesting to you.