UPDATE: Defending Obama: "There are only so many ways to say nothing, after all." My thoughts on plagiarism -- including a defense of Joe Biden on pretty much those grounds -- can be found here, and are excerpted online here. And read this, too.
ANOTHER UPDATE: TigerHawk: "Politicians are not allowed to crib arguments from each other? I, for one, had literally no idea that principles of academic integrity applied to political speeches. . . . If this is the most potent stuff the Clintons have to throw at Obama, they are scraping the wood at the bottom of the barrel."