The cruising speed of a 747 is approx 565 MPH. At that speed it only takes 16 min to travel 150 miles. I'm sure that several of us have been distracted for 15-20 min on a regular car ride and missed a turn or an exit. It's not as bad as people are making it out to be.
Edit: This was an Airbus A320, the cruising speed is between 504-540 MPH. This changes the flight time to 17-18 min to travel 150 Miles.
Airbus A320 | Airliners.net