When you think of up-and-coming social commerce sites, Pinterest may top the leaderboard, but the fast-paced growth of Fab.com means that it should not be far behind.

The site, which started as social network for gay and lesbian users, has morphed into a social commerce flash sales giant that has gained a large following – 2 million users in just seven months.

In a presentation at Business Insider’s Social Commerce Summit 2012 held last week, Sheezan Bakali, director of marketing for Fab, said that the secret to the company’s success is based on three elements: Product, Social Media and Strategic Advertising.

Products That Delight

The key to Fab.com products is that they must delight the customer. We all know from Zappos that happiness is important to long-term customer retention and Fab makes every effort to provide products that exceed expectations. On its About page, Fab says that “exceptional customer service is our most valuable design.”

Social DNA Comprises the Core

Fab’s DNA is social and the company prides itself on keeping customer’s informed about upcoming sales. This “in the know” attitude translates into customers pro-actively sharing the information on Facebook and Twitter. Bakali said that, every 30 seconds, someone is tweeting about a Fab deal.

Advertising Makes Up the Difference

Fab recognizes that, while social media is a potent force in building its user community, the company also invested in strategically targeted ad campaigns. In fact, out of the 175,000 members that joined the site at its initial launch, 50,000 came through ads.