Politico's Ben Smith:

On stage with Oprah and Caroline Kennedy, Maria Shriver (whose governor husband backs McCain) shows up on stage and endorses Obama.

It was, as a reader e-mails, "probably the most exciting thing to happen on C-Span in a very long time."

Shriver said she'd just woken up this morning and decided to endorse. 

“There is no place I wanted to be but here today,” said Shriver. “This election is about a moment. This is a moment not just for the United States of America, not just for the Democratic Party, but this is a moment for California. The more I thought about it, I thought, if Barack Obama was a state, he’d be California. Think about it: diverse, open, smart, independent, bucks tradition, innovative, inspiring, dreamer, leader.”

“But this is a moment. It’s a moment to have a conversation with yourself. Do I believe in an America that's about unity, about coming together, it's about seeing beyond the labels? We’ve got to see beyond the labels that divide us. And if that's the kind of America I want, I think it will be very clear to you what you should do on Tuesday.”

It doesn't get any more Hollywood than this (in a good or bad way).

--Christopher Orr