A recent study from IDC says:

Internet advertising in the United States will continue to grow fast even as the current economic woes will lead to a contraction in ad spending overall, essentially accelerating the transfer of marketing budgets from the traditional media into the new. During the forecast period, Internet advertising will grow about eight times as fast as advertising at large. IDC finds overall Internet advertising revenue will double from $25.5 billion in 2007 to $51.1 billion in 2012.

The Internet will go from the number 5 medium all the way to the number 2 medium in just 5 years, making it bigger than newspapers, bigger than cable TV, bigger even than broadcast TV, and second only to direct marketing. Read More Here.