Yes, it's happened. This morning Oprah Winfrey joined Twitter (@Oprah) during her show. Her first Tweet: "ASHTON IS NEXT!" was very anti-climactic. Instead of hitting Update, Nate Berkus hit Refresh. So it went to Twitter purgatory. Her first successful Tweet:

HI TWITTERS . THANK YOU FOR A WARM WELCOME. FEELING REALLY 21st CENTURY .

Oprah sent six successful updates during the show (9amCT) and none since. She'd already had about 75,000 followers at the beginning of the show. As of 4:30pmET (when Oprah airs in New York), she has 144,000 followers. Many social net-watchers think now that Oprah Winfrey is on Twitter, the platform has officially gone mainstream.

But, is that a good thing or a bad thing?