Hi Joe - The Queen is actually made up of 2 twin beds which are pushed together, but when sleeping on the Queen you can't feel the "crack" down the middle as they put a Queen size pad over the two beds.
If you are first on the list for an upgrade, then I am sure HAL will find you something. I was on a cruise a few weeks ago and a lot of us were upgraded, yet we thought the ship was full. You just never know when the upgrade fairy will make an appearance.
No, having just returned from a 10 day cruise, I won't be on yours. Have a wonderful time and enjoy the Westerdam and Alaska.