Today in Social

That popping sound you heard was no bubble, it was LinkedIn’s IPO – the biggest Internet debut since Google back in 2004. Forget the heady valuation the company set, it’s carrying well beyond that now, which is sponsoring a lot of talk about whether the professional social network is worth it. Matthew Ingram, for one, thinks LinkedIn is less a social network than it is a job site with some copycat features. Fair enough, but besides its careers and job listings business that powers its hiring solutions and premium services revenue lines, it has a pretty healthy advertising business. Its role as a platform is still developing, but LinkedIn may have something to say about professional identity authentication. Meanwhile, Colleen Taylor suggests a few companies LinkedIn could buy with its IPO cash.