InfoWorld, Longhorn backs thick client model:

Not due until 2005 or 2006, Longhorn represents Microsoft’s determination to strengthen its desktop stronghold by fostering a new generation of Internet-aware applications.

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Avalon’s [Longhorn’s 3D GUI] role can be seen as an attempt to raise the desktop ante with compelling 3D extensions to the Windows GUI so that browser apps pale even more in comparison.

For years, Microsoft has argued that browser-based apps are a step backward. The company has suggested these apps be replaced by smart, Internet-aware client applications that exploit all that excess processing power at the edge of the network–that is, desktop computers running Windows.