In its first preview at the Microsoft Professional Developers Conference last year, Windows XP successor Longhorn was shown running a 20-year-old copy of Visicalc. Ancient DOS software won't be the lone occupant of the Longhorn compatibility box. Win32, the Web, and even WinForms -- the .Net era's first GUI framework -- are all legacy APIs from Longhorn's perspective. Their replacements, Microsoft says,
will jointly deliver "the best of Windows and the best of the Web."