Convergence and the Motorola ROKR

In a Slate article, Paul Boutin examines the (at best) lukewarm reception to the Motorola ROKR. He opines that convergence - combining the functionality of multiple devices in a single product - isn't a formula for success:

Motorola CEO Ed Zander recently defended his phone—and slammed the Nano—by saying, 'People are going to want devices that do more than just play music.' I think he's wrong. If Gadget A does one thing well and Gadget B does another, combining them doesn't make for an instant improvement.

Perhaps convergence is yet another marketing instinct that product managers must battle?