That's a regular Microsoft Natural Keyboard Elite. It's a split key format, for ergonomic purposes (read: prevents carpal tunnel or repetitive stress injuries of the wrist). It's considered one of the best split key keyboards, with nice mechanical clicky action. It (the whole series really) is consistently ranked as one of the best keyboards.
It's an off the shelf product, not a specially designed prop.
Source: looking at the one ten feet to my left.