Sega are teasing a new Hatsune Miku project with a newly launched teaser site that reads "New Project (Tentative) Starts On 4/28" placed against a silhouette of the popular Vocaloid character herself.
To date, Sega have released two Hatsune Miku games for the PSP, Project Diva and Project Diva 2nd, while also recently installing the game in arcades. In addition, the Project Diva games have paid HD extensions that can be bought through the Japanese PlayStation Store, allowing fans to play the game in HD and on their TVs.
Project Diva is a rhythm game series that features many popular Vocaloid songs, mostly starring Hatsune Miku herself, although she is occasionally joined by her co-stars in duets or their own individual performances.
Here's a PV of World is Mine, one of the songs from the Project Diva games on PSP.