I recently bought oil-and-gold.com which is a listing of mines throughout the world. It has over 300k pages that are slowly getting indexed. Within 3-4 days after putting it online (and submitting a partial sitemap) to google I started getting 10+ organic hits/day without any off-site SEO (linkbuilding or otherwise). This is definitely good in my opinion but I realize right now there really is not that much on the site to keep the user there for more than a couple minutes. I'm wondering what to do from here. I thought about putting in a user-comments section or something but I'm not quite sure. I do plan on doing offsite SEO here soon but want to have something there that would make the user want to comeback. Any suggestions?