But if you notice, the islands have music that is when you are walking around, and in battle. That way they could use both parts to a song. The slow part with the locket could be when you are walking around Tormenta, and then the organ playing could be the part when you are fighting. I could also see The Black Pearl playing during a Boss Battle. I really think that there are a lot of ways they can apply POTC music to this game. It really isn't that hard. Given enough time I could probably figure out a song to go for each island.

Hmm... the problem is... do they have the rights to use the actual music? Would Hans Zimmer and Klaus Badelt be willing to let them use it in the game? Maybe someone should e-mail them and ask about this music thing.

Here's a short list of some islands and music that could be played on them. The first tune is for when you are simply on the island, the second is for when you are in battle. If I only listed one, they would play the tune for both casual and battle, but different parts of it.

Sailing: At Wit's End, On Stranger Tides (fast part)
Tortuga: Jack Sparrow, Up is Down
Isla Tormenta: Davy Jones (Locket), Davy Jones (organ)
Raven's Cove: Mermaids (slow), Mermaids (attack)
Tavern: Two Hornpipes
Port Royal: [Not sure about casual...], Guilty of Being Innocent of Being Jack Sparrow
Padres del Fuego: [Not sure about casual either], End Credits (from On Stranger Tides)

As you can see, my list is dreadfully incomplete. I'd like to make a pretty full list and then email it to POTCO to see what they think. Feel free to post suggestions. I'd be glad to take them into account.