It should be noted that the Centurion Lounge will start to limit entrance beginning Feb 22. It will only serve as a "departures" lounge and you can only enter within three hours of your departure flight time. I guess this is a result of people camping out for extended periods of time and not being able to handle the crowds. So if your flight lands in SFO and you want to get some work done before you exit the airport, you're out of luck. The person who checked me in last week at the desk there told me that they expect this to reduce traffic by at least 30%.