of course it's not private, you just need to read their privacy & policy and decide for yourselves. I personally benefit from using the platform and don't have nothing to hide from NSA. They maybe make some cash off of me from showing me ads, although I'll never buy nothing from facebook ads. It is a tool that can be used for good. I also think Zuckerberg's intentions are good. He's a good guy and a mentor (not idol) for me regarding business.