Square Enix has announced (via the PlayStation.Blog) that Kingdom Hearts: Birth By Sleep will be released for the PSP on September 7. This fulfills the letter, if not the spirit, of the publisher's earlier promise it would be available in the Summer.
The publisher also plans to team up with Sony to release a Kingdom Hearts: Birth By Sleep PSP Entertainment Pack. The $199.99 PSP bundle will include:
"Mystic-Silver" PSP-3000 system
Kingdom Hearts: Birth By Sleep on UMD (Universal Media Disc)
4GB Memory Stick PRO Duo
Movie (title to be announced)
Square Enix has released a new trailer celebrating the finalized release date, which you can check out right here: