Looks like Disney will start to the production Pirates of the Caribbean 4, aka Pirates of the Caribbean On Stranger Tides, in Summer 2010. And filming should partly take place in Hawaii.

Pirates of the Caribbean On Stranger Tides Trailer

The film is produced by Jerry Bruckheimer, and directed by Rob Marshall. The script has been written by Ted Elliott and Terry Rossio. The release date of Pirates of the Caribbean On Stranger Tides is currently set for May 20, 2011.
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