Wireless communication is eventually becoming a serious stuff in the United States also. As Andrew Bud writes on New Media Age, US carriers are now making premium rate SMS available to marketers and content providers. The market's potentials are huge, with 150 million people that could be reached in the next couple of years.
The problem is, in my opinion, that someone will first have to teach US mobile users what SMS' are. I have several friends who completely ignore the functionality and, if I remember correctly, a research by The Yankee Group considered "active" users people sending at least an SMS a week...
If US carriers don't care about SMS, why should users?