If your site is dropped in/from search results, it can be difficult to find the reason. Webmasters report that using a second-hand IP can be dangerous. Some hosts
forget to remove the DNS for the old domain and your site is indexed by Google under another domain name. Read the "Not the Best NEWS" post by [...]

This may explain why sites with addon domain names rank so poorly in Google:
Google in particular and possibly other engines look at these static and shared IP. As I was explained when I search engine spider first comes across your site it will parse it with basic HTML 1.0. If its able to do this [...]

The Marketing PlayBook posted a very nice quote from the Sun magazine. Enjoy:
“The only reason a great many American families don’t own an elephant is that they have never been offered an elephant for a dollar down and easy weekly payments.”