It was about what I expected for the price - I'd consider Carnival as a low-mid line. It was during Christmas break, so there were a LOT of kids on our cruise (too many for my liking, but they can't do anything about that). Sometimes I felt like I was at Disney. A higher end cruise line probably wouldn't have as many families/kids.
I agree with one other review that I read about the Liberty that at certain times and places in the ship there was an awful stench. Human waste could be smelled in several areas - perhaps they have a problem with their vent system for the tanks. They also have a problem with cigarette smoke. The worse place was the casino. But you could also smell it if you got nearby. Why is the smoking areas not at the back of the ship away from everything else??? We didn't use the casino at all but had to pass by it on the way to other things on the same deck - holding our breaths.
It was Christmas, so the ship was decorated in that theme. They had a really nice Christian Christmas service - possibly my favorite part of the cruise.