... and learned a lot about how non-technical users interact with services like this. Two things:
You ought to consider case-hardening it and offering it as a single-line JS include ... much of your target audience won't want to deal with putting a DIV in the body and some SCRIPT tags elsewhere.
Also: have you thought about using the Pipes Fetch Feed module to automatically discover a user's feeds? Many will stumble over the difference between their profile page: