According to NYC Police commissioner Ray Kelly, 40% of the items stolen in NY are Apple gadgets. Business Insider reported that there were 26,000 incidents of “Apple picking” – muggers stealing iPhones, iPads, and other “smart” devices and then selling them in secondary markets – in NY in the first 10 months of 2011.
Aside from paying attention to surroundings and not flaunting expensive devices, the best way to prevent this is to make the stolen item worthless, or as close to worthless as possible. Carriers are discussing the idea of giving each device a unique ID that can only be used by the owner. To prevent stolen devices from being used on WiFi, meanwhile, it might be possible to allow users (or the manufacturers) to remotely bork the devices if they are stolen–sort of like cancelling a stolen credit card.