What is Open Ground?

The keynote keeps returning to one phrase in particular — Open Ground. In plain terms, what do you mean by it?

“The keynote keeps returning to one phrase in particular — Open Ground. In plain terms, what do you mean by it? For years the whole job was keeping a channel on air. We made that part basically free. So now the real question is what you make with that freedom. That's open ground — and we'd rather build it with people than stand on it alone.”