It's been an amazing summer for Facebook (META -0.54%) investors. In the wake of its earnings blowout, the social networking stock exploded in July, rising nearly 50% in just the last month alone and surpassing the $38 level where the company made its public market debut last year. And unlike its IPO valuation, this recent run-up certainly seems more justified. Why? Because Facebook's management has executed beautifully on most of its key strategic initiatives, most notably building out its mobile advertising platform. In this video, Fool contributor Andrew Tonner argues that while there's a lot to like with Facebook, those thinking of buying today still might not be getting their money's worth at today's prices.