Silverlight is a cross-browser, cross-platform, and cross-device plug-in for delivering the next generation of media experiences and rich interactive applications for the Web.
Eclipse is the most recognized development tool for Java platform application development.
So I'm glad that Microsoft is sponsoring this initiative to integrate the Microsoft Silverlight technology with the Eclipse platform.
Silverlight is already cross platform running on Windows, Linux and Mac OS, so this project is the final piece of the Silverlight puzzle.
More information at http://www.eclipse.org/proposals/sldt/