Maria,
I've been on the QM2 twice in Britannia class, the maiden voyage from Southampton to Florida then a transatlantic last year from Southampton to NY. The maiden was spectacular, lots of positive energy and fireworks in almost all the ports but there were some issues with untrained staff, the food service etc. which is not unusual on a maiden trip. Very much improved in all respects in 2006. It's big but I've never felt like there were too many crowds. Favorites: great promenade deck, always lots of deck chairs for reading and napping, wonderful library, high tea, top notch Canyon Ranch spa (no pushing of products and services), history trail and art around the ship which is fun to tour and discover, Commodore Bar, late night hot tub looking at the ship's wake, tons of activities. I'm not a buffet person so can't really comment too much. More interesting at night when they convert the buffet area to several different cuisines...asian, italian, etc. Chef's Galley is fun for dinner if you're interested in cooking. Small area ...no real decor....where a star chef cooks and chats to a small group of about 15 or so people. Surcharge includes wine pairings. Like Todd English a lot but you must book right after you get on board. There's also a $20 (2006) surcharge here. I think they added the surcharge after the maiden because the restaurant was so overwhelmed that they needed to do crowd control.
It's a thrill to do the Transatlantic. 6 days at sea rarely seeing another ship. The QM2 handles beautifully. It's a joy to watch her slice through the North Atlantic with such authority. Truly an ocean liner, not a fat floating hotel like some of the mega ships. You'll love sailing out of NY harbor (I did several times on QE2). Will post if I think of anything else or you have questions. Marianne