Karen Rogers very clearly states in the Resort Podcast that Davey Jones, part of the next POTC movie, will be making an appearance in the ride when it comes back in June. This begs the obvious question of where he will be seen. An guesses?
My guess, in the fire secene. To the right of the 'flume' there is a great expanse of water that is unutilized, the perfect area to have him rise up slowly and ominously.