If your like me i have struggled with a fps with xna. I can get a slow slow slow 3rd person working but nothing more. Here are some Quotes from the creator Bacon.

So begins the long path to create a FPS engine for the XNA.
As you should already know, the "Banshee Trix" game will evolve into a simple physics engine which will become "Chaos", the engine for Entropy. Chaos, Entropy, makes perfect sense doesn't it? (Chaos is the state of High Entropy)
I will be logging my progress on the forums, so keep checking by. If you know anything about physics, such as formulas for movement and stuff, you are encouraged to talk to me. I won't even be taking Phyiscs until next year, so I'm working off of simple gravity and deflection. -Bacon

Well, I fixed the bouncing, now the banshee reflects perfectly off of the surface it hits.
I also attached the camera to teh back of the shee, much like how it looks in Halo (I even add the reticle)
Holding the left shoulder button displays the original camera, which can still be moved normally.
EDIT:
Here is the newest video, which I forgot to post... -Bacon

Also it works with the pc and Xbox 360! Sorry PS3, Wii Owners.

Here are some vids

Chaos Vid 1

Chaos Engine Beta Vid 1