In China, that day is today.

And the time of the cell phone as wallet might not be far away in the United States either, according to mobile marketing experts.

Already targeted text messaging is taking off here, says Shawn Harris, president and chief executive of SkyWire Media, a Las Vegas mobile marketing company.

Harris talked about how the technological landscape has changed in the last 25 years - from Ataris to PDAs with more power than the first computers - and how marketing through the mobile channel is the next frontier of advertising during the monthly luncheon of the Technology Business Alliance of Nevada at Lawry's The Prime Rib last week.

According to the Mobile Marketing Association, there are more cell phone users - 2.4 billion today - than land line users.

And cell phone users do more than just talk. They text, surf the Web, check e-mail and even shop. Many cell phone users, especially younger users, are never without their phones.

"Marketers love this," Harris said. "Mobile marketing will change marketing like the Internet did 10 years ago."

In fact, more than 15 percent of the 315 billion text messages sent each month are commercial marketing messages.

Nine out of 10 brands plan to use text and multimedia messaging to reach consumers by 2008, according to an independent survey of 50 brand name companies commissioned by Airwide Solutions, a mobile messaging and applications company. Forty percent said they had already used text messaging campaigns.

One-third of those companies will spend 10 percent of their marketing budgets on the medium.

More than half of the brands said they would spend up to 25 percent of their marketing budgets on mobile marketing five years from now.

Harris cited statistics compiled by ABI Research, a technology market research firm, that anticipate the mobile marketing will be a $2 billion industry by the end of 2007, growing to $19 billion by 2011.

Mobile marketing has proven to be more effective than phone calls or e-mail blasts, Harris said, using the example of works his company did with the Hard Rock Hotel.

SkyWire sent out a text to 3,400 locals on a subscriber list offering two-for-one Joan Jett and the Blackhearts tickets at The Joint. Within half an hour, 265 people has purchased tickets based on the promotion.

Texts promoting a Steve Miller Band concert at The Joint were then sent to those 265 people, and 93 percent responded within 10 minutes. Ten minutes before the end of the show SkyWire sent out another text to those 265 people advertising a happy hour special at Hard Rock's circle bar. The casino estimated $58,000 in additional revenue from the text marketing, Harris said.

Mobile marketing is perfect for promoting everything from car dealerships to "American Idol," he said.

But as with other forms of advertising, consumers will not tolerate overuse of their mobile phones to pitch products.

"You don't want marketers spamming you like they did with e-mail," Harris said.

Spamming mobile phones is illegal, he said.

And the MMA, based in the United States but with 400 members worldwide, helps shape standards in the industry as well as stimulating growth in the market.

More than two thirds of cell phone users surveyed said they would find texts that weren't targeted to their interests intrusive, Harris said, versus two-thirds who said targeted messages would not be intrusive.

In fact, 61 percent of younger cell users say they want companies to send them targeted advertising, Harris said.

"They are going to have more and more disposable income," he said. "We have to figure out how to market to them."