RJ,
If you would like to get the maximum life out of your tires, then have them rotated at every 2nd oil change.
In a front wheel drive car, the front tires will look flat and even, as far as wear goes. The rear/non-drive tires will develop lumps and pits, if they are not rotated. This is also dependent on the tire type and quality.
Someone in this thread, said something about being talked into brake pad replacement, when tires are rotated. When your tires are rotated, this is the best time to check your brake pads. If you wait until the metal backing plates hit the rotors, then you will need new rotors (Additional cost). There should be no extra charge to report brake pad life. It should be included during the rotation.
When you have the tires rotated, ask them to inspect the brake pads, and give you an idea of how much pad is left.
GMdude, Former GM Tech.
P.S. There are 3 things that I view as important, personal safety issues, on any vehicle. The ability to stop, steering/suspension components, and good tires.