Hi, My fiance and I are going on Carnival's 16 day transatlantic cruise in late October.
Scoot on over to the Carnival board. We have a group from CruiseMates on this cruise, plus we've hooked up with a bunch of others on the same cruise. Lots going on, and you should feel free to join in!
As for the ports, it's not like the Caribbean where you'll find tour guides offering tours at the pier. If you want to do full fledged tours you'll have to pre arrange it with private companies (Port Promotions and ShoreTours are 2 that I know of), do Carnival tours, or explore on your own via bus or taxis.
Barcelona is a wonderful city, and the hop on, hop off bus is not a bad idea, in that you can be on more of your own pace. A ship's tour, you'll only move as fast as the slowest person.
Palma de Mallorca is fairly easy to do on your own, using the ship's shuttle to town, and your feet.... unless you want to get out of the city.
Same is true of Funcah, Madiera.
Malaga is the only stop I haven't been to. There a few of us have signed up for the Jeep Rally tour with Carnival. It's half a day, and should give us an overview of the area, and a half day to explore on our own.
I'm told the tour to Alhambra from Malaga is a must do... but we passed because half the time is spent on a bus getting to and from.
Hop on over to the thread we have going on the Carnival Message board. Sure you'll get lots of info and opinions there.
Hope we get to meet onboard!