WP7 was released in 2010. Three years later they now have an estimated 3.3% market share. If that's not a failure for company the size of Microsoft, and with the millions spent on marketing, I don't know what is.

I'll never say never, but it's looking pretty much like the Zune. Nice and solid product with some nifty features, but not different enough to dethrone the dominant players.

The problem is that Apple dominates the high-end and calls the shots regarding the operators (that by experience knows that they will lose customers if they don't offer the iPhone), while Google panders to all the OEMs by giving away a very capable operating system with top notch apps, and to operators by allowing them to customize it with crapware.