"It's a simple story, we liked the team.. we liked the opportunity," said Jeremy Liew, partner at Lightspeed Venture Partners. "This opportunity for white-label social networks is actually a very compelling one as we've seen the growth of those social networks, now more than a million on Ning."

Liew, who was a panelist at AlwaysOn's Summit at Stanford this week, was responding to a question asked by Michael Arrington of TechCrunch, who was sitting in the audience. Arrington asked why Lightspeed invested $15 million in Ning at a seemingly absurd valuation of $750 million, a deal first reported by All Things D.

Liew also likened Lightspeed's investment in Ning to Greylock's $25 million investment in Facebook at a $500 million valuation back in 2006.

Watch the video for more of Liew's explanation.