We just returned through Seattle on 8/22 from a Holland America (M/S Amsterdam) cruise to Alaska. We used the Holland America "express disembark" option, which means you carry your own bags off the ship and through the terminal.

We were allowed to leave at 7:15, but we finished breakfast and headed towards the gangplank around 8:00 am. There's a rather long walk to the terminal building, but it was pretty efficiently handled, especially considering that the Sapphire Princess was also disembarking then.

The immigration check was very fast, and while the customs lines were long, they moved quite quickly. It took us about 30 minutes to get from the ship's gangplank through the formalities to the taxi stand, and we were at the SEA airport ($30 taxi ride, but I'm generous with tips ...) by 9:15 am.

The airport was PACKED with people, mostly cruise tourists with *lots* of large pieces of luggage. Getting through that took the mostly time and anxiety, and yes, there wasn't an empty seat on our SEA/SFO flight.

Have fun!