Answer: Excellent question. The fact is there are a few ways to ensure you are chosen as the primary content provider. The best option is to require that all who syndicate your content provides a inline text link directly to your original posting of the article. For example they would say something like this at the end of the article included in a link: “SEO Answers #15 by Ross Dunn”. This way everyone who repost’s your article is sourcing your content as the original.
If you do not source the original release in this manner the website who publishes your article and gets the most attention for it (via links or publicity measurable by Google) will have a better chance of being chosen as the original content provider.
In conclusion, unless you strictly enforce your ownership to the article you may not get the final credit when Google is forced to guess who published it first.
For more info here is an article on article syndication content duplication I recently wrote.