I'm thinking about that, too.
This will be my first cruise, so I have no idea what will happen when I get back, and dh is really excited about the food.
I have a semi-formed plan, though. First, I figure that it is one week, and while it is possible to do a lot of damage in one week, I'm pretty sure I will be able to fit into my clothes at the end of the week, but I'm planning to wear the tight stuff at the beginning.
If I want something, I'm going to have it. That includes bread, butter, etc.
That said, I also plan to work out every day. Again, I've not yet gone, so that plan might be gone after the first day, but it's my starting point. I enjoy working out. It makes me feel good and energetic, and since the gym is at the top of the ship, I'm hoping for some great inspiring views. I usually do both free weights and cardio, and that's what I will likely do.
Second, I plan to take the stairs a lot. Sounds like it's a faster way to get where you are going, and since dh won't work out, I'll bet I can get him to take the stairs to try to offset some of the damage.
Third, the reviews of the food have been hit or miss, so if something isn't very good, I won't keep eating it. This one will be hard, both because of my upbringing and also because my dh gets upset when people waste food. Another food tip I'm going to try is to not have things I can easily find here, like fries or hot dogs. However, I try to eat pretty healthy most of the time, so I don't eat too many hot dogs and I may indulge.
Ultimately, I think I am going to gain weight, both because I will be drinking and also because I plan to enjoy the food, but I'm going to try NOT to turn into the Tazmanian Devil, ripping through the buffets at a high rate of speed and gobbling anything in sight. Then, when I get home, I'll probably spend a lot of time at the gym and eat pretty light for a few days. Let's hope that mitigates the damages!