Geeky geeks geekily track down stolen iPhone

That's great if the thieves don't turn off the application...

As good as the story is, a lot of it relies on iPhone owners having certain settings flipped on, as well as the person who has the phone not knowing the right ones to turn off. For one, they can disable all of the MobileMe features by simply yanking the SIM card out or deleting the MobileMe account from the phone. They can also perform a software restore, which means your data is safely erased, but that you can no longer track where it is without carrier intervention.

This isn't the main thing to worry about though; it's that MobileMe's capability to locate your phone hinges on you having the 'Find My iPhone' setting enabled on the phone itself. This lets the device maintain a constant connection with Apple's servers to provide that neat-o, real-time tracking and instant receipt of messages you send it. With this and push messaging turned off, (both are changes that can be made without any sort of MobileMe, or iPhone password check) the service can no longer locate the phone.

From: http://news.cnet.com/8301-17939_109-10270273-2.html