Details of NSA Data Requests from US Corporations

Facebook (here), Apple (here), and Yahoo (here) have all released details of US government requests for data. They each say that they've turned over user data for about 10,000 people, although the time frames are different. The exact number isn't important; what's important is that it's much lower than the millions implied by the PRISM document.

Now the big question: do we believe them? If we don't, what would it take before we did believe them?