Apr.9, 2003 CNET News.com By Richard Shim Microsoft's Windows CE .Net operating system for devices, such as the Media2Go portable devices, will be used in set-top boxes for delivering content over digital subscriber lines. The software giant made the announcement at the National Association of Broadcasters convention in Las Vegas this week. Manufacturers and developers are initially targeting Asian markets, which have a high number of DSL (digital subscriber line) customers.