It's always a shame when legitimate classics fade into the dusty pages of gaming history, because of bad platform choices or limited release. The original Bangai-O had its roots on the N64, being released only in Japan and prompty forgotten. Later on, it enjoyed an enhanced worldwide version on the Dreamcast... but like the first time around, it was on a fading platform and did not manage to reach the audiences it could have. Naturally that wasn't the only thing conspiring against it since as a absurdly challenging multidirectional shooter it already had a relatively tiny niche of fans to draw from.
Fortunately for gamers, developer Treasure wasn't content to let the franchise die with that. In its surprise DS revival, Bangai-O Spirits retains a very similar feel - you'll control a mecha whose sole job is to unload on enemies with a near blinding array of projectiles and lasers and missiles. When I say "blinding", I mean streams of screen-filling pure energy eviscerating your foes. In the original, you actually wanted to lure enemies into attacking since the more destruction and explosions you cause at a time, the more special energy that will return to you. It's a dangerous give and take that requires reflexes of an almost unholy nature, and for many that's exactly the way it should be.
The DS is in 2D, pushing a plethora of sprites on the screen and literally bringing the system to its knees with significant slowdown. Depending on your perspective, this is a good thing or not... because you'll note in Bangai-O, the slowdown can often give you that split second extra time to plan your next move. This may sound ludicrous, but believe me, when the going gets rough in Bangai-O your fingers are likely to bleed from the sheer ferocity of what is unfolding.
Bangai-O Spirits is still early in development, and there are probably plenty of refinements to the formula waiting to be unearthed. But as far as announcements go, this was one of the very best of Tokyo Game Show 2007.