I believe drtravix has parsed United's pdf timetable. I looked at doing the same thing when I was developing CoMETS. I, too, was surprised to find discrepancies between the pdf timetable and what was actually awarded. Expedia and Orbitz each had slightly different distances, too. The only source that seemed to match the actual mileage credited was the mileage listed on united.com when viewing a proposed trip by schedule.

For any Mac users who might be interested, CoMETS is now available for Mac OS X and it's a great way to keep track of miles, EQMs, BIS, segments, and EQS--by the month, quarter, year or lifetime. It also includes a nifty mileage calculator--I dealt with the mileage discrepancies by allowing you to enter the correct mileage; this will be retained for future trips.

If you download CoMETS (it's free), you will need the password: ftcomets