LivingSocial, the company behind Facebook apps Visual Bookshelf, ReelSocial, DiningSocial, and their corresponding websites, has closed a $5 million round of Series A financing led by Grotech Ventures and Steve Case. The LivingSocial team, led by Tim O’Shaughnessy, are Revolution Health expats, which is chaired by the AOL co-founder.

LivingSocial is a great example of a company that got its start on the Facebook Platform and has since launched on MySpace, Bebo, hi5, Orkut, and now their own websites. The company did not disclose what portion of is traffic comes from each platform.

What is clear is that the company took advantage of the opportunities for user acquisition on social networks – over 6 million users have created more than 80 pieces of content on the LivingSocial network since its launch less than 1 year ago. Achieving those kinds of numbers out of the gate before the Facebook Platform would have been unheard of.

“The support of Grotech Ventures and Steve and Jean Case will help establish LivingSocial as the leading social discovery and cataloging network, a centralized, user-managed community where people can organize, review and share what they are most passionate about,” Tim O’Shaughnessy, CEO and co-founder of LivingSocial, said in a statement. “Based on the sheer number of reviews we already have on our site, there is no other interest-based community with the volume of user-generated cataloging, and we’re just getting started.”