I can't find the link now, but just read an article last week regarding a study Facebook did back in 2010 (I think?) to see if they could have an effect on voter turnout. They didn't have a large effect on the turnout, however it was measureable. Kind of creepy to think of the power these giant tech companies like Facebook, Google, Apple, MS, etc... could really have/or perhaps already do over our political system in regards to how they could influence voters.