I'm not broke thank you very much!
I could buy one by myself, but the "problem" is I never felt I had to use a keyboard on my xbox... though I understand perfectly it will be useful in this case. I'm still considering it like a cool console and an awesome media center, but plugging a mouse/keyboard in it sounds more PCish to me.
Besides, my last keyboard is my trusty Keytronic which is still PS/2

But as I see emails and posts and stuff about "when will there be kb/mouse support?" keeping coming I'm beginning to consider this "investment", so relax

As I said earlier this looks obvious to do anyway, I have a very clear idea on how to do this, so I'll add the code -providing it doesn't break things- and it might actually work out of the box.