Yes, that occurred to me during the show last night. I only saw a tiny bit. People have booked tickets so potentially he has access to their names, addresses and seat numbers. Assuming that a reasonable number of people have distinctive names, you can find a fair bit of information about quite a few of them using the interweb that will bring up stories in local papers, etc.
Wasn't there something about someone winning a house. That would be all over the Interweb.
Edit: reading some more posts above -- Oh, yeah, and Facebook and stuff!