Andy Beal has a short post about how to avoid Google's duplicate content filter when syndicating your blog content.

"..If you syndicate your content on other sites, make sure they include a link back to the original article on each syndicated article. Even with that, note that we’ll always show the (unblocked) version we think is most appropriate for users in each given search, which may or may not be the version you’d prefer."

This would seem simple to do - but what I worry about is people stealing my content and not attributing it to me - have seen that happening a couple of times lately - so there is no backlink to my content - and it's not attributed to me. That's not good but I have no evidence anything bad happened (except I get upset what I see this kind of thing).   At least Google is telling me not to worry:

"….Don't worry be happy: Don't fret too much about sites that scrape (misappropriate and republish) your content. Though annoying, it's highly unlikely that such sites can negatively impact your site's presence in Google. If you do spot a case that's particularly frustrating, you are welcome to file a DMCA request to claim ownership of the content and have us deal with the rogue site. "