We sailed from Southampton to Cape Town - the first leg of QM2's current world cruise. Generally, once everyone (passengers & crew) settled down, it was a fine experience. The ship was full and, at first, things didn't run too smoothly but by the time we reached Madeira everyone was more or less au fait with what to do and where to go etc.
My wife wasn't too happy with the dining experience in the Brittania restaurant, constantly complaining that the food was indifferent but I was less critical. Feeding 2,350 people at two sittings in the evenings will never be more than mass catering.
The entertainment was pretty good (Louis Hoover was outstanding and put on a "free" third concert in response to the acclaim he received). Some of the lecturers were fascinating (Martin Saunders, a BBC wildlife cameraman, for instance, and Peter Hawthorne on Afrikaners - standing room only for that one). There is a fine library on board and the planetarium films were amazing. Each day seemed to pass in a flash - there was no excuse for being bored though some people were.