QM2's Captain’s Cabin is located behind the bridge on deck 12 Starboard Side.
It is not as large as the QE2's or as well appointed, although it is very nice! (think QM2 Queens Grill Cabin without a balcony)
It is not large enough to do cocktail parties, so on QM2 they do not hold Captain’s Cabin parties like the used to on the QE2.
Interestingly, the deck officers all live on Deck 4 forward, unlike on the QE2 where the used to live on the boat deck!
Personally I used to like the Deck officers accommodation on the QE2 because every cabin was different and had been on the receiving end of 'personalization' from many previous occupants... and of course, no deck officer cabin was more than 30 meters from the Wardroom!