My first "oil service" indicator finally came on, after 10 months and 13,160 fast miles in mostly very hot weather. Of course I've changed the oil and filter at least four times already, with a few quarts added in between changes over that time. Just a data point for those who would rely on the service indicator lights to keep an expensive engine healthy.
Richard BMW CCA Sin City Chapter '00 M5 '88 M3 (3K between oil changes, still cheaper than new engine)