Microsoft and Nokia are betting their future on the Lumia 900 for the very clear reason that they're getting squeezed out of the smartphone market. But AT&T's decision to go big on the phone to the tune of a $150 million advertising campaign is a bit more surprising. Their concern, as illustrated above, is that having lost iPhone exclusivity Verizon is catching them in subscribers.
But if AT&T's problem is that losing iPhone exclusivity is a problem because iPhone is a uniquely valuable platform, then talking about the Lumia 900 doesn't solve the problem. Conversely, if Windows Phone is actually superior to iPhone then (a) iPhone exclusivity isn't that big a deal and (b) AT&T is doomed anyway because they don't have an exclusive right to Windows Phone just to this one particular Windows Phone product. Meawhile, common sense says that AT&T's actual problem is its reputation for having an inferior network to Verizon's and the forward-looking problem of offering LTE in fewer markets. That suggests that the $150 million would be better spent on upgrading network infrastructure rather than marketing.