It's Biden

John Cole says:

BTW- The pick is probably gonna be Biden according to the media, who I rate as the person most likely of all the VP possibles to call Mitt Romney an asshole. Others are hoping for a casual “m____ f_____.” Either way, I call that a win.

Megan Gogerty says:

The best thing about Biden, though? He's so articulate. And clean.

I say Biden is a smart, if safe, choice. By "safe" I mean that he isn't the face of CHANGE, or anything so romantic and exciting as that.
He's a white male with a gazillion years in the senate, and a face and a name easily recognizable by much of the country. He's got foreign policy cred, and sort of a tough guy persona. And as the press is deeply concerned about "seriousness" -meaning things they hear and approve of at the right cocktail parties- Biden is likely a press-friendly choice. Over the years, they've probably been to a lot of the same cocktail parties and shared space on campaign buses and planes zooming off to serious foreign policy meetings.
Also, while he's not mac & cheese boring (Bayh), he's reassuring to people who can't handle the very radical idea of a black president and a woman VP- too much too soon! As much as we'd like to believe the country can handle it, there are an awful lot of nervous nellies out there, press and citizenry, for whom that idea would be just so frightening.

(Aside: I don't mean that I wouldn't have supported a "scary" choice. In many ways I think it might be a case if not now, when?)
I have watched too many senate hearings to love Biden. But I like him. And he can get mean- he should be great in the VP debates. And as for his tendency to say really amazingly stupid things: we're running against McCain here, a walking gaffe machine. I think that takes the heat off Biden somewhat.