If you would like an in depth look at the changes and implementations to the Vista interface, this is certainly a great place to start:

All the interface changes that come in the Vista package are a direct or indirect result of Vista's new graphical subsystem. Code-named Avalon but now officially called Windows Presentation Foundation (WPF), Vista's graphical underpinnings should prove to be a boon to both developers and end users. But it won't be just the Vista community that benefits from WPF because Microsoft has decided to backport WPF for Windows XP and Windows Server 2003.

Developers will (and, by all accounts, already do) love WPF because it provides a one-stop shop for all their graphical needs. Before WPF, developers had to work with a rather alarming number of technologies and application programming interfaces (APIs). For example, to draw a simple 2D shape, they called on the Graphics Device Interface (GDI); for 3D objects, they used Direct3D or OpenGL; for media objects, they used DirectShow; and for user interface objects, they used USER32 or Windows Forms, to name just a few. Some of these technologies (such as the GDI) have been around since Windows 1.0. Clearly, it was time for a change.

With WPF, developers can do 2D, 3D, animation, imaging, video, audio, special effects, and text rendering using a single API that works consistently no matter what type of object the developer is working with. This greatly simplifies user interface programming, resulting in more robust applications that are delivered to market faster than ever.

WPF also introduced a new markup language called XAML-eXtensible Application Markup Language-which acts as a kind of front end for building application interfaces. The idea here is that by using relatively simple markup code, developers and designers can work together to build user interfaces.

From the user's perspective, the main problem has been that although our graphics processing units (GPUs) have been getting ever more powerful, and our video adapters have been populated with more graphics memory, our operating systems and applications-with the notable exception of the gaming sphere-have not been programmed to take advantage of all this powerful hardware.