Microsoft is already paying developers for porting their applications from iOS and Android. This is all well for the developers but what about the end users. They have already invested a lot in the apps on those platform. So the cost of switching is not just the hardware/carrier-contract cost but also buying all those apps again for WP7. Also, what happens to all the data that is stored in the apps on other platforms?
Microsoft, here is an idea for: pay extra to developer to enable importing data from other platforms. And make all those apps free for the consumers who already purchased those apps on some other platform.