There are a lot of spammers in the internet who steal your content and put it in their website or spam blog (splog). The content in their blog is not original. They get it from your blog via RSS and pass the content to their blog. Spam blogs do not provide any real content for users. Splogs have become a major problem on free hosts such as Google’s Blogger. By one estimate, about one in five blogs are spam blogs. These fake blogs waste valuable disk space and bandwidth as well as pollute search engine results. If they link back to you, it could be trouble if google consider their blog as spam. Their link to your blog can have bad impact on your Pagerank, because bad blog is linking to you.
Here is how you can tackle them. Always put some kind of identity to your blog. You could link back to your own blog article or put your name or blog url as a signature for the article. You can report splog to SplogSpot.com, a splog blacklisting service.