Soul Calibur IV Steelbook?

[Vinland]

I recently picked up a steelbook of Soul Calibur IV (PS3) on ebay. I honestly don't know much about it and I was hoping one of you guys might be able to shed some light on it.

What I know:
-It's European (I think)
-It's a promotional item of some sort
-It has an Xbox 360 counterpart

(By the way, I'm new. So, hello!)