Yahoo and MSN put more emphasis on the on-page factors(eg keyword density, location etc)
Google puts more emphasis on the off-page factors (esp anchor text of incoming links) and quality signals (eg on links to viagara sites; crosslinking; etc)

If you doing OK in MSN and Yahoo and bad in Google, then this means one of three things:
1) Be patient as you sandboxed (if new site)
2) Get more links with keywords in anchor text
3) Fix the quality signals (eg who are you linking to)

In your case, its probably due to your proliferation of spammy interlinking/crosslinking network of sites:
http://www.webproworld.com/viewtopic.php?p=159909

CBP