“The Buck Stops Here” for Content Duplication
As a general rule of thumb…
Do not reproduce third party articles on your site. Google may hold you responsible for duplicating material. Remember the lines of responsibility — you are held directly responsible for what is on your site.
You are less liable to get in trouble if others ask to reprint one of your articles on their site and you allow it. But…
1) Make sure they have a decent Alexa (Definitive Guide to Alexa) and Google PR (use Search It!‘s popularity query). Or it should at least be a terrific site. (Try not to be biased against a young-but-great site — its Alexa and Google PR will come eventually.)
2) Ask these other site owners to clearly label the content as a Reprint with credit to you and your site. Google should be able to recognize language like that. Plus, if the other site ever outranks you, you have something to show Google.
3) Include a link to your site (which is why you care about #1).
The only reason that you should allow an article to be published on a third party site would be to get a good-quality inbound link.
As always, focus on creating your own quality content. Building a solid “unique-voice” content foundation/blueprint is your first priority…