With mobile advertising poised to surge in 2007, Verizon wireless - a brand among the nation's most advertised - intends to seize the opportunity and itself become an ad medium.

Banner ads will begin appearing on news, weather, sports and other websites that users visit via their Verizon mobile phones, reports the New York Times. Verizon officials say they are being cautious by limiting where ads are displayed and excluding standalone video ads, which customers find intrusive.

Cell phones are both personal and widely owned, so marketers' messages could, in theory, be tailored to and targeted based on demographics like age, gender and location. But there's a shortage of data about whether the ads motivate consumer behavior.

"There's still a question of cost and value," said David Cohen, EVP and U.S. director of digital communications for Universal McCann. Because of a lack of inventory, CPM rates average around  $40, compared with $10-$15 on the web, he is quoted as saying.

Mobile ad spending should total some $150 million in 2006, up more than three-fold from $45 million in 2005, according to Ovum Research, which projects that mobile ad spend will reach $1.3 billion by 2010.