CBSSports.com said on Tuesday it is opening its live Internet broadcast of the NCAA Division I Men's Basketball Championship tournament to other web sites such as Facebook, YouTube, Yahoo Sports and ESPN.com.

Live events streamed via the web have had a fairly checkered history dating back to the Victoria Secrets fashion show in 1999. User demand overwhelmed the technology back then. Subsequent live events on the web such as the NASA shuttle launch, Pope John Paul II funeral, and the Live 8 concert, all in 2005, have fared a bit better.

But March Madness on Demand, which first tipped off on the web in 2005 as a live subscription event, has since evolved into the seminal free, live, annual, American broadcast event on the web.

CBS generated $250,000 in revenue for the 2005 streamed event. In 2006, CBS, which bought the broadcast rights to the popular tournament in 2003, dropped its $19.95 subscription fee and switched to ad revenue only.

The network set new traffic records and took in $4 million in 2006, and in 2007 attracted 1.3 million unique users and made $21 million in total revenue, according to CBS. Akamai, which is one of the firms supporting March Madness on Demand, said its network peaked at a rate of about 500 gigabits per second.

"The more fans that have direct access to March Madness on Demand through the web site of their choice expands our reach exponentially and continues to grow the impact of the championship in ways never before possible," Greg Shaheen, the NCAA senior vice president for basketball and business strategies said in a statement.

With the opening of the 2008 broadcast to other web outlets, CBS is expecting record demand for the web broadcast of the tournament.

The visitor demographic which is youngish, mostly college-educated, and male tends to be attractive to marketers.

The network has signed 30 advertisers for the broadcast including AT&T, Coca-Cola and Pontiac.