This tidbit comes from a lawsuit filed by the United States Olympic Committee and the IOC:
For security reasons, tickets to the Opening and Closing Ceremonies have been specially designed to prohibit, to the greatest extent possible, counterfeiting and speculative ticket reselling. Specifically, each ticket to the Opening and Closing Ceremonies for the upcoming Games is embedded with a microchip containing the ticket’s serial number, which can then be read by a database maintained by the [Beijing Organizing Comittee for the Olympic Games] to retrieve the bearer’s photograph, passport details, addresses, e-mail address and telephone numbers.
Sounds like fun. Hopefully, the lines to get into the stadium will move faster than the ones to get inside an Apple retail store to purchase an iPhone 3G.