For anyone consider the QM2, I would clarify with them what the costs would be...I was under the impression that it might be about even, even with a pricier fare for me (rather than airfare), since the fees for the pets would be lower.
However, not only was the fare for a single person insane (more than the quote for the pets + myself on a plane together), they also wanted me to book 2 kennels per pet...one for the cat, one for the cat's litterbox (?!), and two for my dog. That brought their fare up to $1,600 by themselves, plus my fare.
The facilities did sound nice, though, FWIW (the kennels seem fairly roomy - especially when they charge you 2/pet! - and they have a separate area where you can take your pet out of the kennel and hang out with them). Your pets will still be left alone, however. Apparently "visiting hours" are limited to set times, so you won't be able to hang out with them 24/7 or anything.