I flew on Virgin American to Portland, Oregon, last year and had to stop in San Francisco on my return journey to Chicago. The layover was over 2 hours long, and I spent that time relaxed in the new Terminal 2. The terminal has great window coverage of the airfield.
I saw for the first time an Airbus A380, the largest of the so-called jumbo jets (is that phrase even used anymore?). It was flown by Lufthansa (see photo).a
I also saw a lot of Boeing 747s from different airlines, including United, OneWorld, Star Alliance, British Airways, and Cathay Pacific. I may have seen a Chinese airline.
I also saw President Barack Obama land in Air Force One. I recognized the plane from far away, as it was coming in for landing, but I wasn’t completely sure until it touched down. My camera was probably hanging around my neck; I was too dumbstruck to do anything about it. After it landed and I was positive that Boeing 747 was flown by the United States Government, I walked around the terminal until I could see it.
The plane had been parked far away from a terminal, near a hanger and two C-17 military cargo planes.
American airports should have viewing platforms. Not just plane spotters like to photograph them. Amsterdam Schiphol (AMS) airport has a viewing platform and there was over 50 people up there, including lots of families.