Has anyone faced this? SEO Gurus please help me if you can.

I have a site with 300 sub category urls each pointing to one US city, targeting keywords like, say, new york city bookstores, hartford city bookstores etc, and until around mid August 70% of these urls were ranking in top 30 for their specific main target keyword, but then suddenly within a day almost all of them got dropped below 100 and some much lower. They still are not back and I simply dont know what went wrong or what I can do to fix it. Is there a way to somehow get them back in 2 weeks?

I will appreciate any and all help. If you have any guess what's going on, please respond.

Thanks a ton!

You may have been hit by a human reviewer. How good was your content?

Thanks for your reply. The site content was good and in fact I have 50 state urls that are still ranking well. These have similar quality of content and went through the same seo implementation as the city urls, but only the city ones got dropped.

I did massive social bookmarking and forum links to get them to rank in the first place and used a backlink indexing tool to get the backlinks indexed. I wonder if this had to do anything with the rank drops! But then again the question remains how the state urls are still doing just fine!!

If anyone is interested in taking a look at the site, pls mention your preferred way to have me send you the site link privately and i will do that. If there is a promise to get the ranks back again for about 40 cities or so in the next 2 weeks, i am happy to spend money as well...pls let me know.

Thanks a ton!!