It's the best pirate game I've ever played. It's also one of the very few pirate games I've ever played, so I dunno if my review will count for much.
Surprisingly addicting open-world pirate game where you can go out and do random stuff, like rescue your family from this villain, go treasure hunting, attack other ships and/or settlements, acquire goods from one port and selling it at another port (trading), and even wooing (and eventually marrying) a random daughter of a govenor. There's fun mini games (although lots of people hate the dancing one) and you basically play until you grow too old to continue pirating. Keep watch of the morale of your crew at sea or they may end up deserting you!
Only bad thing I found with the game is that the main character whom you play as doesn't look manly enough for my liking, and while I like the dancing mini-games, it tends to go on for too long. If it was a shorter mini-game, it would've been much better.