Mickey Alam Khan has written an editorial @ Mobile Marketer titled 'How to answer skeptics of mobile marketing.' You should read the whole column, but here's an excerpt:
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Mobile, for some strange reason, encourages armchair gurus of all persuasions to pass judgments on the channel, sometimes without the immediate benefit of facts at hand. So let’s make a case for mobile by asking the same question of other channels that is asked of mobile.
You'll have to find Mickey's analysis by clicking here, but suffice to say, the man makes a strong argument, coming at the skeptics from a novel angle.