The newest Hatsune Miku title's official name and release date have been revealed by Japanese publication Famitsu. It'll be called Hatsune Miku and Future Stars Project Mirai and will release next March in Japan.
The title was originally referred to as Hatsune Miku Project Mirai (which actually means 'famous' in Japanese). Sega has not offered a ton of information on the title as of yet, but judging by the trailer, it follows Hatsune Miku through various activities including dancing and playing piano. There also seems to be 2-D platformer elements, but again this is only based on what is seen in the trailer.
Perhaps the addition of 'Future Stars' in the title suggest that Hatsune Miku may be sharing the spotlight with more friends. Hopefully more information will be sent out once Sega makes an official anouncement.
Hatsune Miku and Future Stars Project Mirai is set release on March 8, 2012 in Japan. There will be a limited edition version of the title which includes an adorable Nendoroid Puchi figure. Be sure to check out the extremely adorable trailer for the game below: