No, Space Invaders Extreme is anything but expected, much to the invaders' misfortune. You'll blow away the poor buggers with splash-bombs, quad-shots, and all manner of high-powered defensive weaponry. These weapons each sound out random musical notes when fired, all within the key of the particular music track, allowing you to lay down a funky beat during your defense.
Occasionally you'll earn enough points for a bonus round, which mixes up the gameplay by sending enemies streaming down the screen, requiring the player to take out a set number of the foes. After these are defeated, you'll be seamlessly kicked back to the normal gameplay mode. The action never lets up, lending it a feel of a game like Geometry Wars.
It sounds absurd in its implausibility, but for pure arcade fun, Space Invaders Extreme is looking like a fresh take on the original concept. While no US release has been announced, it seems inevitable. The game will make its way to Japanese stores early next year, so keep your eyes out for news of a US release in the meantime.