Facebook Inc (NASDAQ:FB) 's IPO still leaves investors with a bad taste in their mouths, and the company's stock is still down almost 38% from its initial price. I don't believe that the company's business model gives it a durable competitive advantage over other social media sites, but its certainly better than Zynga Inc (NASDAQ:ZNGA) 's. Zynga Inc (NASDAQ:ZNGA) is a company that either succeeds or fails based on its partnerships. It's not dependent on itself, but rather on others. Groupon Inc (NASDAQ:GRPN) may actually have the best business model of these three companies, but that doesn't mean that it has performed well or provided investors with a superb valuation.