I think he does one of two things:
Leaves the seat vacant as a smackdown to the disloyal Republicans that derailed Miers nomination or, nominates the staunch conservative they've asked for.
If it's the former, we know Miers was a serious nomination all along...the latter, she was a throw down nomination intended to call negative public attention to the nomination process in the hopes the public won't tolerate a repeat of the nonsense.
Just a thought; but, obviously, I've already been wrong on this.