I think it's an interesting notion.
The data point I'd want to look at involves the degree to which these web-enabled phones are used for searches, as opposed to checking email, looking at breaking news, downloading ring tones, uploading photos, etc.
Once we reach a critical mass where we know people are searching for our services -- to enhance some kind of event -- via mobile phones, then creating mobile sites specifically for view on smartphones makes perfect sense.
Right now, I'm still working to maximize my internet marketing capabilities with search engine optimization, social networking, and PPC. That's a full plate there already.
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