Ning, the social network software company, has raised a venture round of $15 million, putting the company's private valuation at $750 million, Kara Swisher reports tonight.

Last September at MIT's EmTech conference, I asked my old pal Jason Pontin, editor of Technology Review, to interview Ning CEO and co-founder Gina Bianchini. We have republished the interview tonight.

Yesterday, published Gina's history of social media essay.

Andy Plesser, Managing Editor