Comic-Con 2006: "Pirates 3" Clip Spotted and Described
From IGN FilmForce (with spoiler warnings!): "Also seen were some glimpses of the new character Sao Feng, played by Chow Yun-Fat. There were also shots of a large sea battle, with Captain Jack displaying some of his non-traditional battle tactics. There were also shots of swordfights, and scenes with dialogue that show the traditional Pirates of the Caribbean humor will also be present in this sequel. Every major character that appeared in the first two films seemed to appear in this clip, so it would appear the series will be going out with a big bang."
See the rest of the report here.