I'll mention the other Brazilian ports here as well. Salvador de Bahia is a beautiful old crumbling place. It's been made a UNESCO World Heritage Site, and I can see why. But I think they may have left it too late--buildings really are crumbling and many seem beyond compare. And the hot, humid climate makes upkeep a constant activity. I will watch and see if they manage to restore this city, but probably would not go back.
Fortaleza was a brief stop, with just a bus shuttle into the market to shop for a while. So did not see much. It also is very hot and humid, but seemed less so than Salvador. The beaches looked beautiful, and there is lots of money flowing into this town with many new luxury condos and hotels.