Ok, not to be too morbid, but let's compare the present Supreme Court justices with the Social Security actuarial table and make a prediction about how many more nominations (by death) the President will get (excepting Miers, whatever happens with her). Let's simplify and give Bush three more years in office and round the justices' ages down to the nearest year.
|Justice||Age||Chance of living three more years|
|John Paul Stevens||85||65.1%|
|Ruth Bader Ginsburg||72||92.5%|
Chance of all justices surviving three more years: 41%. Plus, justices often retire without dying, so it's pretty likely that President Bush will get at least one more nomination.