“Apple has made it possible for almost anybody – a jealous spouse, a private detective – with access to your phone or computer to get detailed information about where you’ve been.”
Pete Warden who, with Alasdair Allan, has discovered that Apple’s 3G devices keep a record of your locations (precise latitude and longitude) indefinitely. The data is on the iPhone or iPad (3G version) and in the iTunes created backup files on your computer.
And indeed it is!
Warden has an app you can download (Macs only) and see for yourself. You run the app on the computer where you have been backing up your iPhone or iPad.