The delay game

I'm about to leave for the airport to fly across the country on a United Airlines flight. Anyone care to place bets on how much of a delay there will be? With UA, I've found that it's not a question of if the flight will be delayed, but how long. (At T-3 hours, they claim the flight will be on time.)

I'm going to be optimistic and say that it's going to be between 15 and 30 minutes late. However, I predict that the trip back is going to be delayed at least an hour.

Edit:
Scorecard:
Departing flight left on time. Shocker. It was, however, compensated for by extreme proximity to the flight's standard-issue screaming baby, and a comically inept car rental employee who wasted a bunch of our time when we got there.

Returning flight sat on the runway for about an hour. On the bright side, I slept through the entire ordeal.