Longhorn Developer Center has some nice articles about the upcoming Windows generation just like the german C'T of course.

Great architectural interals I found interesting:

WinFS : the new filesystem thats based on a MS SQL Server variant (sort of a light-version of the database – if you can call 22 megabyte runtime "light") deploying transactions and integrity features to every desktop in the future… Oracle and others take care about this… I guess this move will be the root of future juridical fights between Microsoft and the rest.. read on in the WinFS-discussion or at this winFs article

WinFX Aero: : a new GUI paradigma? or at least new fancy icons designed by the great usabilty labs at MS (who else has the cash to fund a few thousands of usability testers ?) – checkout this samples from the PDC 2003

WinFX Indigo : the new web services framework – code name Indigo for this framework, provides rich support for service-oriented design that is complementary to traditional object-oriented approaches. Indigo marries the best features of .NET Remoting, ASMX, and .NET Enterprise Services into a unified programming and administration model. Indigo's deep support for standard protocols, including HTTP, XML, and SOAP, makes it easier to integrate applications and services without sacrificing security or reliability. More

NGSCB : Next-Generation Secure Computing Base – is new security technology creating sort of a sandbox (called Nexus or Nexus Mode via Nexus Abstraction Layer (NAL)) inside the windows-system to make sure high security is provided for applications that need it. NGSCB will be integrated into a future version of the Microsoft Windows operating system as a subset of Windows functionality. The whole thing is not yet ready and a couple of open questions remain – just read on

XAML for GUI : describing the GUI in a formal XML way is what we every dreamt of – it seems like Windows Longhorn is going to deliver such features – a preview chapter explains creating such an app with the typical HelloWorld sample.

Application Model : Features of the "Longhorn" Application Model:

The "Longhorn" application model defines what an application is:

• Its entry points
• Its flow of control?how to navigate from one page to another
• Its shared state and resources
• Application-wide events
• Its isolation from other applications

The "Longhorn" application model defines how to deploy and maintain an application:

• Deployment as single or multiple files
• Update, rollback, and administration

The "Longhorn" application model defines the user's experience with the application:

• Zero-impact installation
• Stand-alone (Windows-style) or integrated in browser
• Runs online or offline
• Navigation model

more in here