"A plug on Oprah is ordinarily a sign that a product has crossed over into the mainstream."

Remember back in 2000 when Oprah told the world how cool 3com's Audrey internet appliance was, and within a year nearly every family in America had one? Man, those things were sweet! Oh, wait...nevermind.

Still, given the success of her book club, I wouldn't be surprised if Oprah did good things for Kindle sales.