Kingdom Hearts: Birth by Sleep was released in Japan two weeks ago on the 9th of January and sales are looking good for the PSP exclusive title.

Reports are showing that the game has now sold over 623,000 copies with no sign of sales slowing down. It's no surprise really when you consider the fanbase behind the Kingdom Hearts series and high scores from reviewers such as Japanese magazine Famitsu with a 37/40.

It is certainly good news to hear that the game is doing so well in Japan, it may even prompt Square Enix to finally reveal a date for the Western release.