I have a directory site with states, cities and business in them. There are many pages that look almost exactly the same, except they have different listings on them. But there is no really striking, quality unique content... It's just like a yellow pages or yelp listing site. My site was hit by Oct 14 Panda update. On Oct 21, the traffic came back 100%. Even though it's a 2007 site, I never built links to it until Nov 18th. I did a link push. Then on Dec 1st, I started building wiki links and comments. On Dec 6th, the site crashed back down to pandalized rankings. Any suggestions on how to panda-proof a yellowpages-type directory?