Hi there Aaron,
I'm certainly not a professional XNA developer, but a co-worker and I are putting together a pet project that's going to explore potential compatibility between XNA and Silverlight. We thought it might be interesting. I blogged about my first app in Silverlight here, and then about adding inter-object collision detection here. We're JUST getting started, so my experience with it is limited, but what did you want to know?

http://geekswithblogs.net/robp/
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