I finished out 2008 with 6,406 miles on the bike versus 4,922 for the car. I was hoping for a few more bike miles, but bad weather and a child in the hospital put me behind the wheel more often than on the wheels in December. Total vertical feet was just under 400K (392,200).
High mileage month was July (698). Not surprising since 150 of that was in one day (RAMROD). What was surprising was November was the second highest (681), when all I was doing was riding to/from work and some longer training rides on the weekends.
This year, I'm going to track miles walked in lieu of driving. The definition is a little loose, but includes trips to the local grocery store (1 mile each way), and to the sandwich shop at lunchtime (not totally legit, since I bike to work and have to walk to get lunch anyway).