Microsoft announced earlier this week that, along with the release of Vista, it is porting its Windows Presentation Foundation framework to Mac OS X as well as for handheld devices. Microsoft calls the project Windows Presentation Foundation Everywhere (or WPFE).

Windows Presentation Foundation (WPF) is a user interface toolkit, mainly based on a Microsoft version of XAML language, that will be made available to .Net programmers so as to create powerful user interfaces for Windows Vista.

Porting WPF to the Mac means that Microsoft will also have to bring a big part of its CLR to the platform. We can also expect the company to make extensive use of the technology in future versions of its Mac software.

WPF will probably also help other companies than Microsoft to port their Vista applications to the Mac easier, as usually the biggest part of a standard application's development is the user interface.

It also means all of these WPF based applications will have a Windows Vista look even if they will be running on Mac OS X' Aqua user interface.

There is already a port of Microsoft's .Net CLR on Mac. It's called the Mono project and it is widely supported by Novell as well as other companies and developer groups commited to Linux.