Web Forefront

But unlike its counterpart -- Windows Communication Foundation / Indigo -- which aims at unifying behind the scenes middleware -- web services -- functions, in the end translating into more streamlined development; WPF/Avalon seems a tougher sell.

In due part because of a special markup language named XAML ("Extensible Application Markup Language"), which is at the heart of WPF/Avalon. In its most far reaching definition, this newly minted Microsoft markup states that "No longer will organizations be required to support multiple languages, such as HTML, Flash and PDF". In other words, another panacea in the world of display formats.

Lets take a closer look at an XAML snippet and its corresponding output :

<Window xmlns="http://schemas.microsoft.com/winfx/avalon/2005"> <Button Width="260" Height="200"> <Image Source="C:\WINDOWS\Web\Wallpaper\follow.jpg" /> </Button> </Window>

Sample source A Guided Tour of Windows Presentation Foundation

The snippet seems powerful enough and innocuous -- 5 lines and a sharp window with buttons. But notice that the markup looks like an embodiment of HTML 4.01, in other words, a mix of data and presentation characteristics.

Standard bodies like the W3C have gone to great lengths to separate presentation from markup issues, with CSS and XHTML. Heck, even other Microsoft products have realized the benefits of this separation Themes and Skins in ASP.NET 2.0 .

But on top of this, you add the need to have an execution environment for visualizing the markup -- in the form of a plug-in or some other form -- and you face an uphill battle in convincing any user base.

Lets face it, even under "controlled" environments and after years of presence, the Browser has yet to provide 100% compatible visual rendering across various clients, making the Windows Presentation Foundation / Avalon a tough sell, at least for web bound interaction.