A great game that gets marred by a few frustrating elements.
The main thing that makes this a Sid Meier's game is that the gameplay is entirely open. If you choose, you could sail the seas sinking ships and never progress towards finding your long lost relatives. The setup is pretty simple: sail a large world map and when you choose to attack other ships the map zooms in and allows you begin firing. Your ship can be upgraded at the ports, each port having one upgrade that it can give. The upgrades allow your ship to move faster, take more damage, shoot different cannon balls and so forth. Treasure maps can be found that lead you to the buried treasure from the other 9 pirates in the game (all of whom can be found and killed). The other aspect of the game is finding the map pieces for your lost relatives and the lost city. You get pieces of the map by hunting down Baron Raymondo from hot tips given by governor's daughters should they take a fancy to you. The daughters will also give you gifts that can keep your crew happy at sea, or make you a better fencer.
The downsides to the game can be overcome with a high tolerance to frustration. Wind only blows one direction throughout the Caribbean so sailing into the wind tests your patience. Also, your pirate ages with time and his skills begin to decline (this ranks high with me as a negative because this is a gaming pet peeve of mine). Getting older really dumps water on this game's fire as sailing between ports can take several months and you find yourself wondering where all the years went. In summation of my review, the game is worth playing and combines a few different styles of gameplay into one neat package. The drawbacks are mostly based on my playing style, and I'm sure they will be no problem for some gamers. If the drawbacks do keep you from enjoying this game to its fullest, I'm sure you'll be glad you played anyway.