I had 130,000 miles on the rear pads in my 2000 and they showed very little wear. Hardly ever used them. I had problems with the rear brake at 5,000 miles, and had the rotor, pads and maybe caliper replaced. Service manager advised not to use the rear brake as they seem to be troublesome and don't do much anyway.
I think I replaced the front pads every 15-20,000 miles.
On my new 2006, the brakes are linked, so I expect the fronts to last a little longer and the rear to be replaced more frequently, even though I just apply the front brake lever. I've got 9,000 miles on the bike and about to take a short trip. I better check and see how they are doing.