With Vita on the horizon, the PSP is on its last legs. That isn't stopping NIS America from localizing and publishing a quirky shooter for US and European release. Black Rock Shooter: The Game is part of a larger trans-media series in Japan, spanning an anime and several manga series. While all are set in different timelines, they all focus on a mysterious black haired girl who possesses a blazing blue eye and a powerful cannon that can shoot rocks at high speed."
focalbox “This is a title that many fans have been waiting for and it definitely lives up to the hype," NIS America producer Jack Niida said in a press release. "We have not finalized a release date yet, but we are working hard to get it out as soon as possible."
Oddly, while the game has been announced for US release, the anime that inspired it has not. You can still read up on the animation on the English language official website.
For an idea of what to expect, here's a gameplay trailer (via Andriasang):