My wife and I joined family members for a planned three generation cruise. We have both sailed to Alaska from our hometown of Seattle before on Holland America, but this was our first experience on a Disney ship.
Staterooms - Well designed for families, certainly ample space in our 4A room for two people. Wave phones make communication easy on ship but we didn't really use them. TV shows the same movies over and over, but at least in the Alaska voyage carried more cable channels than we were used to on other lines. Room stewards were great, left towel animals every night along with chocolate. Biggest complaint was that our suitcases didn't fit under the bed.
Entertainment - The Dreams show was great, and I also would recommend seeing Toy Story. Others had mixed appeal since the audience was geared toward families. The ship band was quite good, the assistant cruise director did a wonderful job running trivia games. Adult entertainment after 10pm was readily available and surprisingly well attended.
Food - The weakest part of the cruise, in my opinion. We have sailed on Holland, Princess, Norwegian and Disney and that is the order I would place the food at least in the main dining room. If you like good food, make as many reservations in Palo (brunch or dinner) - the $20 is well worth it. Plus the extraordinary setting (and absence of kids) gives parents and non-parents alike a great break.
Facilities - The adult areas of the ship were quite vacant. The gym was a bit busy on sea days in the morning, but otherwise equipment was readily available. Do not forget the Outlook Lounge - a very scenic reading/resting area for adults. Also the forward Quiet Cove area was another great area although the cold weather limited its appeal. I wouldn't let the abundance of families discourage cruising as adults can find plenty of things to do as well as quiet places to relax.
Families - Disney charges more than most lines for their cruises, and I believe the extensive children's programs are a big reason. Everything from character opportunities, Princess events, to Kids' Clubs will make your kids forgot about parents. Parents will also have a great time enjoying the complementary babysitting, but non-parents will be stuck paying part of the bill.
We enjoyed sailing with Disney but without being part of a multigenerational family vacation, would probably not sail again.