I'm not particularly worried, Google and Facebook have two of the best security teams in the world and spend an amazing amount of money to protect customer data. The amount of convenience I get from Facebook and Google outweigh the risk I'm exposed to in my opinion. If Governments want to create data protection regulations I'll save my opinion until I see whatever regulation is proposed but I think it'll be difficult…
The fact that they have the best engineers and the best infrastructure, doesn't mean that they are able to find all vulnerabilities and fix them in time. The only way to do it, is to have a proof that system is secure which is beyond our reach today.