One of the most misunderstood concepts in the blogosphere, websites and SEO is what duplicate content filters are and how they affect your blog or website.

Here is a short description of duplicated content which we found a good one:

"Search engines only penalize sites in very specific circumstances and where there is gross negligence.
The short explanation of duplicate content filters is they are out there scouring the Net for spammers and mirror sites gaming the system to increase advertising revenues and search engine positions for specific terms.
They are NOT out there heavily weighing your personal site against your blog or news system. They are basically looking for EXACT or NEARLY EXACT replicas of your site on the Net."

Here's also a nice video we found that may clear even more of duplicate content: