It is better to see Metro as a layer on top of the windows OS. It isn't really competing with desktop apps, but with web pages. The average consumer has more

It is better to see Metro as a layer on top of the windows OS. It isn't really competing with desktop apps, but with web pages. The average consumer has more tabs than windows on their taskbar. Windows is becoming irrelevant. Microsoft wants to coax people away from their web browser, and back into native apps. A closed app store is a good way of offering that in a secure, simple, and profitable way. Desktop apps never succeeded in all three of these things.