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To put it in two words ... the response is too early for a user to judge Windows 8.

The / / build / conference I just came back from, is a developer conference. It merged the PDC (Professional Developer Conference) and WinHEC (Windows Hardware Engineering Conference). The sessions on the agenda are topics spanning from the Framework.NET and new WinRT, to the driver development in user and kernel mode.

Microsoft had to show the Windows 8 user experience along with all the new features and in fact we have seen the new shell based on the Metro-style but this is still a developer preview and so it's still too early to draw conclusions on the end-user experience.

The new user features in Windows have already been announced on the Sinofsky's blog when announced of the two shells and the other details about the increased usability of the old shell.

As announced in the first keynote Marketplace is still under construction and this means that a user, in this moment, can't take advantage of the Metro-style exprience. The only Metro-style applications are only the one pre-installed in Windows. Some of these (like twitorama) are still incomplete although very attractive.

I appreciated the coexistence of the two shells. This choice provide users a new generation of applications without renouncing a proven functional operability within Windows, useful to power-users.

The old desktop is still there and has been improved by adding new capabilities to improve its usability. The new Metro-style shell has a number of advantages for users:

• Applications are available on the marketplace. The idea, originally started by Apple, is certainly an easy and convenient way for finding new applications. The markeplace provide a centralized way to minimize any potential damage that an application can cause.
  
• The applications are packaged in a single file (apex) which contains everything the application needs. Packages are self-consistent and installation / uninstallation is only a matter of adding / removing the package and nothing more.
  
• The package contains, among other things, the manifest that is used by Windows to know which API categories the application wish to use (network access, webcams, local storage, etc.).
  
• Applications can use a new base API (WinRT) or local kind of services called "Contracts". This way, each application has the ability to use the Search functionality of the system, share a resource on a social networking etc.. etc.. Of course these functionalities are subject to the user approval.
  
• The application lifetime is managed more like a portable device such as mobile phones or tablet. The operating system can reduce a process to "suspended" so that it does not consume resources.
  
• Metro applications can only use features that are compatible the Metro-style/mode.
  
• Metro applications must be smooth and can't block the main thread. In other words, Microsoft decided that Metro applications should never have to call library functions that block the current thread for more than 50ms.
  This decision can apparently have a rather limited relevance but its impact is huge. It has direct implications on the usability but also on the whole developer echosystem: libraries, languages ​​and tools which I will discuss in other posts.

In my opinion, Microsoft provided a very convincing response from the technological point of view, guided by the two most important factors: the hardware available on the market and the user requirements.

• Hardware is the driver for the top-performance demand. The new features of CLR 4.5, the new WinRT runtime and the renewed role of C++ were all related performance/power management choices.
• Users asked usability, security and more device typologies. As a result Microsoft created Metro-style where packages, Contracts, Windows for ARM based CPU and asynchronous management.

Wrapping up, users have a platform that is potentially very powerful but in absence of the Marketplace and applications it cannot be judged. It would be totally wrong to judge Windows 8 using a tablet that currently must necessarily use the old Explorer desktop.
The technology platform will be judged not only by developers, but also by the application quality that will be on the market. If the vast majority of applications in the future should offer little functionality or recurring problems, it would mean that Microsoft did not provide sufficient tools to build good applications. I am personally convinced of the opposite because the technological choice do convince me.

In the next posts I will discuss in detail these and other points under the point of view of the architecture of the operating system.