Mrs. Moose, I wanted to ease your fears a little too. We cruised Alaska in 2002 and had no problem back then using our cell phones.
We stayed overnight in Anchorage prior to our cruise, and I heard my cell phone beep at about 4:30 am letting me know I had a message - my mom had forgotten about the time difference.
In fact, I remember having a long conversation with my mother while I was in Juneau. I even called my husband who was on the ship to meet me at the restaurant next to Taku Fisheries to have lunch!
Plus, I'm sure service is even better now. You're going to have a wonderful time. Alaska is amazing!