It was a truly lovely cruise, ten days of mostly heavenly things. Here are some comparisons:
Embarkation: Princess - Ft. Lauderdale - I dislike this terminal, the way they operate, most all of it. But having said that you can go straight to your cabins.
Carnival: Miami is much better, the people are nicer, the terminal more comfortable, the entire process is better.
Shows: Princess - nice costumes, lovely theatre, poor singing and dancing, much less in the way of production shows. Only one comedian and it was in the theatre also instead of a show.
Carnival - fabulous production shows, great costumes, singing, dancing. Comedy clubs most nights also. Much better. The seats in the theatre are more comfortable on Princess.
Food - Both delicious. Both have cut back but there is still plenty and it's all still great.
Room service - here Princess is far better, you can have hot meals, soups, pizza, all sorts of things sent to your room.
Carnival is good but very limited.
Pizza- Princess wins this hands down with their hand tossed pizzas. Wonderful. Carnival pizza is more card-boardy.
Towels - beach- Carnival towels are much nicer but you have to keep up with it, Princess lets you have as many as you want and no threat of having to pay for a lost one.
Bathroom amenities - both have the same layout and small showers. Princess has lotion, shampoo, and conditioner in bottles and nice soaps too. Carnival has hit and miss things but they do have the shampoo dispenser and body wash dispenser in the showers. No conditioner though.
Staff - both fabulous but Carnival wins because they all know your name, I don't know how they do it but they do!
Shops onboard - the same
Beds - I like the bedding on Princess better but had to get a foam topper because the bed was too hard without it. Both are nice.
Cabin - Carnival cabins are larger but not the balconies. Both are very nice.
Ports - When you come back on Princess they are out there with chilled wash cloths before you board the ship, when you are hot and tired and ready to drop this is VERY nice and costs almost nothing.
MUTS (movies under the stars) - Princess wins this hands down. They come around bringing you blankets, popcorn, pizza, warm cookies and cold milk and padded lounge chairs. VERY nice.
Casino - the same but Princess had one completely non smoking night and every table was filled with people all night long.
Guest services - Carnival wins hands down. Princess needs retraining here, and lots of it.
Final morning Carnival wins for several reasons. One, you can get room service and not have to brave the elevators full of people with suitcases to have your coffee and roll or whatever, Princess stops room service the evening before. Also Miami is SO much better than Ft. Lauderdale here again. They have luggage carousels in Miami where Ft. Lauderdale just lines up the 5000 suitcases and you have to go find yours in that mess.
If I have forgotten anything just ask and I'll let you know. Would I cruise Princess again? Probably not. I just like Carnival better.