Just completed my final long run in preparation for the San Francisco Marathon (August 3, 2008). Distance was 20.7 miles as I did the usual 5 mile loop course 4 times. It was hot. Started a little after 2 PM and used my house as the aid station (water and gel). Anyway, pretty smooth. Mild knee pain and stiffness towards the end but I feel I am ready for San Francisco.
As a bonus to the run I went over the 1,000 mile mark since I purchased my Nike Nano in April '07. Nike 1000 Mile Club.