Cheating isn't a good enough reason to chop, hack, slice, dice, or otherwise effect the removal of vital male components.
That's not to say the bastard doesn't deserve it, but come on, you'll be over it in a few months and he'll be unable to have children the rest of his life. Not a fair trade.
Edit: I forgot...I want Oblivion too, but then again, I already have it pre-ordered for PC.