I'm also going on Celebrity Infinity on Aug. 30th, first time to Alaska too, can't wait. I understand the passengers will be a little older, but I think we'll fit in just fine. I love Princess and RCCL, so I'm also hoping I love Celebrity and I hear the scenery in Alaska is something else.
You may also want to check out the prices we have going for this Cruisemates cruise, they are the lowest I've seen them:
Hope you do decide to join us :-)