Led by Microsoft's Bill Gates and Google's Eric Schmidt, the U.S. high-tech industry is well represented at the World Economic Forum, which opens Wednesday in Davos, Switzerland.

The event offers business and political leaders an opportunity to schmooze in a mountainous setting, and it gives executives like Gates and Schmidt -- fierce competitors in their daily business lives -- the chance to let their hair down.

This year, discussion will focus on what organizers are calling the "Shifting Power Equation" by identifying business shifts that climate change could cause.

At the event three years ago, Gates predicted that spam would disappear as a problem in two years. Obviously, he missed that prediction, although Microsoft has made strides in combating spam. The spammers are making great strides, too.

Gates also missed his prediction three years ago that Microsoft would catch Google in search technology. "We will catch them," he said, according to media reports at the time.

This year, Gates will discuss philanthropy.

As for Google, CEO and chairman Schmidt is scheduled to be joined by the firm's two founders, Sergey Brin and Larry Page. At last year's Google-sponsored event, Brin lectured guests on the Middle East. Google's YouTube unit will be represented by its chief and founder Chad Hurley. A few months ago, Hurley was still building the struggling startup before it was acquired by Google for about $1.5 billion.

Google is making a strong presence this year as a co-sponsor of the event, which is expected to have 2,500 participants. Participants were charged about $35,000 this year to attend.

Google will host a gathering Friday night at the Kirschner Museum, but Gates will get the last word in. He hosts a breakfast meeting Saturday morning with Tom Friedman, a New York Times columnist and author of "The World Is Flat."

The atmosphere at the event this year is particularly upbeat, as illustrated by a PricewaterhouseCoopers survey released Wednesday of more than 1,000 executives. Ninety-two percent said they are "confident" or "very confident" about their prospects this year. That result is the highest rating in 10 years.