If you are thinking about booking a cruise with Celebrity, I suggest you look at Holland America line or some of the all-inclusive cruise lines like Azamara, Silverseas, etc. You'll probably snare a better value.
This isn't so much a review of the Constellation, which is a very nice ship, as it's a review of Celebrity management's policies. The prices for beverage packages, drinks, shore excursions and specialty restaurants are astronomical. I was on the Summit twenty-two months ago and loved it. There, a martini didn't cost, with gratuity, over $16.00, which was the price on the Constellation at the popular Martini Bar (somewhat less at other bars).
Celebrity's penny-pinching practices are all too obvious and quite annoying. Here are some examples: if one wanted olives and a stalk of celery in one's $10 Bloody Mary, one had to request them. Likewise, if one wanted cocktail snacks while sitting at a bar, one had to ask for them. For dinner in the main dining room, four nights out of five we had green beans, once with carrots, twice with carrots and broccoli, and once with peas and broccoli. Are all other vegetables too expensive? The dinner portions were rather small, so I always ordered two starters, a salad and some kind of soup.
No complaints, except that it is small and needs more electrical outlets.