The two things I find compelling about wireless are ubiquity and opportunity. Wireless phones are everywhere. Throughout the US and the world, more people have mobile phones than have PCs or TVs. This will take some time to get resolved and it needs to be done right to avoid the problems that faced the online advertising space. The carriers also have significant interest and control in this area.
Wireless advertising is only as good as size and reach of the medium.
I think the inflection point for the wireless Web comes when we get to 2.5G and 3G networks. Wireless has the potential to be effective as both a branding and direct marketing medium. The bigger promise, however, is in the direct marketing area. This benefits consumers by providing them with relevant information about products and services they want in their vicinity. It benefits merchants by improving the communication channel with the consumer.