Mouse and Keyboard support.

[moycon]

I've heard a few express interest in a mouse and keyboard for the 360.

Cuurently you can hook up a keyboard, but just for use on the dashboard. It looks like a 3rd party has come out with an adapter that lets you use a keyboard and mouse in-game:

 

http://xbox360.ign.com/articles/747/747585p1.html

 

I'm just wondering if that would give those folks an advantage in the FPS games.

[Atariboy]

If the titles support the device, I don't see why it wouldn't be an advantage. A mouse and keyboard is widely considered as the best way to control first person shooters.