Metro apps will only be available on Windows store
The Metro applications for Windows 8 will be available only on Windows Store as reported by Microsoft. The centralized distribution will allow better discoverability, easier enforcement of software trials and facilitation of in application purchases for those applications. Microsoft would get a 30% cut of every sale through the Windows Store and will take it upon itself to test each submitted application, this pretty much like the Apple’s Application Store or Microsoft’s own Windows Phone Marketplace.
This will provide a kind of one stop location for software that they can trust and provided with a well-defined division according to how things have traditionally worked on the platform. The traditional desktop applications on Windows 8 will continue to be available as the usual channels like the developers website, the download portal, so on. The windows store will also provide a free listing service for the non-metro Windows application.
Developers would have to pay a nominal fee in order to upload a Metro application to the Windows Store, including the trial versions. Five PC license activations will be offered to the customers who purchase an application from the Windows store.
Enterprise customers will have the privilege to download and install Metro applications independently from the Windows store and can use the applications for testing purpose and even deploying them across many computers.
Though these terms were not officially disclosed by Microsoft but were accidentally revealed them when its “Primer for current Windows developers” went live. All the details were preliminary and are subject to change and Microsoft will be treating distribution of Metro applications the same way it treats Windows Phone 7 applications for mobile devices.