I just got back form a five day cruise on the Jubilee. It was our first cruise, and we absolutely loved it. The ship was clean and well kept and looked a lot better than I had expected for a 15 year old ship. The staff were wonderful and the entertainment was really good too.
I had heard mixed reviews before I left also, but don't pay any attention to them. Just go with a positive attitude, and you wond be dissapointed. It's the best kind of vacation because they plan everything for you. All you have to do is decide what you want to do that day!
Have a great trip.