It may bev worth stressing that this is for PCs and not for phones - that wasn't a typo in there. In the same way that Apple users can download content for their computers since the desktop app store launched in January, Windows customers will be able to download software for their computers straight from Microsoft's own shop.
Echoes of the nineties
Those of us of a certain age will remember fondly the last time Microsoft was so obviously inspired by Apple, when it adopted the mouse for Windows when Apple had been advocating it for quite some time. Of course the software marketplace has been established on the phone for various vendors for a fair while so this isn't quite the same but it smacks of everyone following Apple once again.
Microsoft has hinted that it will nbe more flexible about how participants can accept payments than its rivals.