If I remember correctly, Ning raised their last round at a ~$400M valuation. As a freemium Facebook competitor with Pmarca involved, you can sort of understand, but no one is going to pay >400M for a B2B social network maker.
People who put $119m into Ning either believe there will be a bigger sucker to sell it to (hey, AOL is still around) or are the kind who reads Wired & TechCrunch seriously and get star struck when a Valley celeb attaches their name to a company. That's really all there is to it.
