Old thread, but still valid. I change the brake pads on all six of my motorcycles every year. Some bikes get new pads twice or three times a year. I do not ride that many miles, but I do approach fast and brake hard. Wiggling the rear before a turn is not uncommon for me, even on the XD (more so on the Panigale and cafe racer).
Old pads can glaze over and create excessive heat, causing risk to the rotors. Pads are so cheap that it is not worth it to try and make them last tens of thousands of miles unless you are touring and don't use them much. I change my brake fluid several times a year, as well.