Update: In related news, Sony Europe has said that the delay is "only applicable for the Japanese market".
Original story: Sony has said that Gran Turismo 5 will not be released in Japan this March after all, and in fact it doesn't know when the game will be released.
Gran Turismo 5, originally announced at E3 2006, has been in development for 400 million years, but the threat of its slip-slidey release date becoming a complete joke looked to have been alleviated when the company announced a March date during the Tokyo Game Show.
Things also looked to be going well given the launch of the GT5 Academy Time Trial demo on 17th December, which had been downloaded one million times in Europe, Australia and New Zealand according to an announcement yesterday.
Sony has blamed the latest delay on ambiguous production issues, according to Reuters.