"He wouldn't just shore up Obama's foreign policy flank. He would help Obama go on the attack, which is surely a consideration when running against a candidate who still supports an unpopular war," writes Thomas Noyes in the Guardian.
Here's the clincher: "In terms of temperament, Biden is hot to Obama's cool - a useful quality for a candidate more inclined to seek common ground than go on the attack." This is a brilliant point: Obama needs a guy who will fight hard and tear into the substance -- or rather, lack thereof -- of the McCain platform.
Moreover, Biden is at once charismatic and gracious; in a word, he looks like a statesman. What more could Obama ask for in a running mate? In a vice president of the United States?