Today my site has dropped from 2nd & 6th to 74th & 97th for my 2 primary keywords. When I do site:domainname.org the pages of my site are still listed with the exception of my index page, which is what I'm pointing 95% of my backlinks at. Site is 3 years old, PR4 and the only backlinking I've done in the last month was add it to 3 blog networks. The 3 blog networks have been drip feeding the backlinks for the site for the last 2 weeks, with another 2 weeks of links to be dropped. I'm fine with the site dancing but deindexing my index page has got me worried. Any ideas or advice? Thanks.