I haven't seen anything yet except for aftermarket square fog lights that could mount in there with some work involved. I think that piece is attached to the rest of the bumper, so you'd have to cut it out to replace it with something else. Or just stick something over it with like double sided tape.
If you don't want the factory fogs, I think the 09-10s look a lot cleaner without them compared to pre-09s. Pre-09 had large holes just asking to be filled with something, not so much with 09-10.