The movie is currently slated to hit theaters on May 28, 2010, just in time for Memorial Day. Other cinematic releases around that time include Dreamwork's Shrek Goes Fourth and Marvel's Thor.
According to the site, Prince of Persia's previous June 19, 2009 release date would have placed it in close proximity to the next Michael Bay-directed Transformers sequel, Revenge of the Fallen.
Loosely based on the 2003 Prince of Persia game The Sands of Time, the Jake Gyllenhaal and Alfred Molina-starring film was written by series creator Jordan Mechner, with Mike Newell (Pushing Tin, Harry Potter and the Goblet of Fire) directing and Jerry Bruckheimer serving as producer.
Thanks to K1Bond007 for the heads up.