I know at least one fellow that has over 100,000 on his!
For fun I poked around the for sale ads to see what the used ones had on them. On cycletrader.com, the average for '08's seemed to be 3000-4000 miles, highest mileage '08 on EBay was 9500, highest in this sites classifieds was 9550 (a dealer demo).
I found this older thread from the site
whats-high-mileage-spyder