They don't want you to use the desktop. But they have to keep it in for a while, because they haven't yet been able to get the users into the clouds.
That is what metro is for. That is why they keep ramming it at you. It will take a while and there will be interim steps.
The desktop programs will be in the clouds. There is no actual desktop on your machine.
They have turned the laptop into a phone. The user can make calls, video calls even. The user can swipe across a few icons, jab one and the MS cloud server does the rest. It might be quite small - credit card size, for example.
That would be fitting considering how much the users will be paying. It is all controlled by MS of course. You can only do/run what they allow. Lots of privacy issues as well.