Just returned from a transatlantic crossing (Southampton to New York) aboard the QM2 with the family. It was my first cruise and exceeded my expectations, just wonderful from top to bottom. I thought food and service in the main Britannia restaurant was top notch, wasn't so impressed by the canteen/buffet, but only used it at lunchtime. Didn't see the the point of spending more at the speciality restaurants. Particularly enjoyed pre-dinner drinks at the Commodores Club.
Entertainment was also very good - something for everyone - while the cinema was better than many you would find on land. Planetarium good as well.
Cabin, yes small, but very comfortable.