We have taken 2 day ferry boat rides in Asia and Europe and mostly disliked the experience. This was our first "cruise" and we loved it.
First, the Disney Magic is just a beautiful ship. Designed with graceful lines and wonderful art deco elements, our first impression was that of a classic 1920's hotel like the Waldorf Astoria, or Rosevelt in New York. The ship was built in Italy and has graceful curves. Parked next to a Celebrity ship, the others simply look like mid rise condo buildings on a boat hull. The Magic is aesthetically exciting. Our room was near the center of the ship and we sailed through moderate + seas on the fringe of hurricane sandy with no discomfort. The design of the ship and the stabilizers keep things smooth and quiet. Parts of the ship show a little "patina" but IMHO it is about as perfect as anything that sees 2,000 guests a week can be.
Inside, the designers of the ship were generous with stairways and elevators, making it very easy to find your way around (and easy for elderly guests and those in wheelchairs). The Magic is filled with classic Disney art and you will still be discovering delightful design elements and details throughout your cruise.
While some of the special effects are becoming a bit dated, I can assure you will be dazzled by a few of the entertainment elements built into the ship. (I'll not mention my favorite so you can be as surprised & delighted as I was during one of the Broadway type stage shows). For movie buffs they have all the recent Disney movies running through a rotation. The Walt Disney theater has the best 3D imaging and sound I've seen anywhere. Topside fireworks with entertainers rappelling in to the dance floor during pirate night was exciting to experience.
The best part of a cruise on the Magic has to be the crew. From Capt. John and Cruise Director Peter to Charlie who cleaned our room, each and every one made us feel as though our kid was special and we were their best friends. My wife speaks seven languages and was conversant with most of the staff in their native tongues. They all reported that they genuinely enjoyed working for Disney and were well taken care of. I particularly had fun with the small groups doing animation classes and crafts. (Angelina, Wayan, Brittany, Fred ... thanks!)
The food was nearly always good and sometimes astonishing. Generally, the seafood selections were better than the beef. The rotational dining plan keeps your hosts with your family and they quickly adapt to your tastes & preferences. By the last night one Chef had even gone out of his way to make a special dish common to my wife's home town! (I don't know that DCL approves of such activity, but it gives you a feel for the enthusiasm of the crew). They would let me pick seafood from the morning buffet (optional, but quick) and make an omelette from items I had sourced elsewhere. That flexibility impressed me. Can't decide between the Lobster, the Veal, or the Beef? They may just overwhelm you by bringing you a bit of everything on the menu to sample & enjoy.
The music on board was exceptional and it would not surprise me to see the next "Justin Timberlake" come from a DCL entertainer like Seth Gibson. We all enjoyed the Disney Characters and their frequent costume changes kept seeing the characters new (hey, there's Magic Mickey, or Pirate Mickey, or Capt. Mickey etc ...) Some of the dance moves showed remarkable athleticism.
For the older kids and adults, the spaces were so popular we'd see folks sometimes running from place to place with big grins on their faces; excited to share the next event. Most of the friendly people we talked to said they were really surprised at how much their teenagers came out and just had fun. This allowed them to retreat to the more romantic parts of the ship for nice husband and wife time.
I feared life without an internet connection and being trapped on a ship for 7 days. After the cruise I'm wanting to do a 14 day trans-Atlantic crossing with no ports of call, just to enjoy the Disney Magic and her incomparable crew.
Top Tip: Gaveston isn't was popular as Port Canaveral, but probably easier to get to! Save money, fly to Houston and take the 1 hour Disney transfer to the ship. We found it easier than Orlando and saved money.