This goes out to all of my industry peers out there who want the secret answer for figuring out how to use mobile marketing. I'll officially let the secret spill.
It doesn’t matter.
You’re wasting your time and your clients' money developing it and hypothesizing about it. Stop wasting your time talking about it. Finding new ways to intrude and irritate on the last vestige of privacy won’t succeed in the direction anyone is currently pursuing. Phones are more and more relevant and marketing aimed at reaching people using them is less and less viable.
Why not? Because though cell phone users have reached critical mass, even those whose phones are capable of accessing the web currently choose not to. Only 5% of those who are capable access online content. This is because what is available to access isn’t worth the trouble. All of this will change quickly, however, because the number of people using Smartphones will dramatically increase in the coming months. As this happens, led by the launch of the Apple iPhone with an integrated full-scale web browser (all websites will be viewable as-is), mobile becomes the same as online.
It makes it pretty easy. All you have to worry about is creating engaging content and maybe adjusting some usability to work on small touchscreens such as the Treo and the iPhone rather than through full-sized keyboard/mouse setups. In a matter on months, the integration of content will be to the point where all the content we access, and the advertising messages that surround it, will be the same regardless of which screen (television, computer, phone) you’re enjoying it from and the conversation will stop being about one medium versus another. It will be about what it should always be about—creating great experiences for those who want to learn more about a product or service.