Patches take time to code and implement. Now, for most companies the time is measured in hours. However, there is a definite cynicism among players toward developers that they turn a "10-minute fix" into a "3-month eventuality".
Edit: So far, XBL is banning folks who are caught using it, but I haven't seen anything about those who use it on PSN, so I can't comment there. I also heard that PC users would face 0 repercussions for this exploit (though that's hearsay).
At any rate, the patch will come eventually, just give it time. In the meantime, I hope you're not one of those who would utilize such an exploit. Those are the worst sort of people.