What you see in the video is authentic NiGHTS. Sega hasn't changed it into a minigame collection or a training game or even a 3D platformer. They didn't give him a gun and a car. This is a real sequel to the Saturn game in 2.5D, just like God intended. Ignore the Disney-esque narration and flourishes in the trailer. They are irrelevant.
For some reason, these videos aren't embedded at Gamespot's NiGHTS page, despite using the Gamespot player. You can, however, download a high-resolution version of the gameplay video there. They are embedded after the break. Please watch them and improve your day!
[Via NeoGAF; embedded Gamespot videos found at GoNintendo]