Sorry to keep going on about Pirates, but Jim and I have come up with a possible theory for something that could be revealed in the last movie.
We re-watched Black Pearl and Dead mans chest on the weekend and noticed this. While visiting tia Dalma's "hut" Jack steals a ring from a table with jewellery on it, but leaves a silver heart shaped locket and chain. Later in the scene where Will is attempting to steal the key from around Davey Jones neck whilst he is asleep at his piano/organ, they zoom in on a identical locket, open and playing "romantic" music. This got us thinking, who is Tia Dalma? Think about the spelling of her name................play around with the letters and you get Matildaa.................could she be the one that Davey Jones loved, lost and still grieves for????