NBC Universal TV czar Jeff Zucker says the Today Show could expand to four hours in the future -- but not this year.

"This brand continues to be unbelievably strong," he tells Gail Shister. "The third hour has been a huge success. There's no reason to believe it couldn't keep going."

But: "I would not rule it out down the line. It's not going to happen in the next year, probably two."

> Aug. 8: Four Hours Of 'Today' In The Future?