If your blog contains large amounts of content found on other more "senior" blogs or websites, Google will lower your search engine rankings and eventually de-index your entire site.

This fact is really important if you are creating blogs that post articles from other sources, or blogs that contain news items from RSS feeds. In this case, there are many other blogs using that same content and competing with your site for indexing on Google.

So what's Google to do?

What happens is that the sites with the most "authority", trust and PR will take the top spots. The rest of the lot will be left to fight it out at the bottom, and eventually get de-indexed. These are usually new sites with lots of duplicate content.

So How Can New Sites Compete?

One way new sites can ensure their longevitity in the search engines is to avoid publishing large amounts of duplicate content. When you make your content as unique as possble, you won't be competing with other sites because your content is only found on your site and Google loves that!

The problem with this is that it takes time to modify each article or feed item manually.

This is the reason I created the Synonymizer Wordpress
More infos
http://synonymize.com/
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