This is a good white paper on the duplicate content debate. It's covered in Article Marketer links, because it's supplied by them, but it's got good info, and Article Marketer is a killer product anyway, so what-evs. Enjoy...
h**p://www.mediafire*c0m/?miq3k0nnedz
h**p://www.mediafire*c0m/?miq3k0nnedz