It seems Google have changed their algorithms as changes are occurring across  SERPs. Webmaster World is currently discussing the changes and from  what I can gather it seems like a whole heap of  Yahoo links have been dropped – or there’s  some sort of error in Google not being about to read them past the first page.

Follow the outcomes here http://www.webmasterworld.com/google/3563627-2-30.htm#msg3569053