It’s fine to consider Facebook members the product, but that’s not how Facebook presents itself. It presents itself as a personal networking site oriented around the users, so it’s not surprising those people would want some say. If you’re selling widgets, those widgets don’t have an opinion on how they’re marketed or who they’re sold to, but we’re talking about people here. If Erik’s point about people being the product is true, then Facebook, Foursquare, et al. are not just incompetently explaining things to their members. They’re deliberately obscuring the issue. There’s a reason they call the form you have study participants sign the “_informed_ consent” form. Can you imagine what people would say if the forms listed “sell your information to online marketing firms” as a possible use of your data?

There’s a difference between publicly funded research studies and private companies, but the standards for ethical treatment of people don’t vary depending on who’s doing it.

It is a marketing problem, but the problem they’re trying to solve isn’t disclosure. It’s “How can we continue to get away with this?”