Obama loves Ludacris and it is going to give the National Republican Party fuel for those quasi negative ads.
Or I can see this as the swift boat issue sponsored by some shrewd McCain backer.
From the AP
Ludacris' "Politics as Usual" alludes to an imminent victory for Obama by handing out major put-downs to his rivals. It dismisses Hillary Rodham Clinton as a vice presidential candidate — "that (expletive) is irrelevant"_ and says presumed Republican nominee John McCain doesn't belong in "any chair unless he's paralyzed."