It’s easy to ridicule the estimated 2006-or-2007 ship date for Longhorn, the next major release of Windows. But do you doubt for a moment that Longhorn will provide more improvements from Windows XP than desktop Linux will gain during the same period?
Early versions of Gnome and KDE were pretty much just clones of the Microsoft Windows UI. They’ve diverged since then, and I’d say Ubuntu’s default Gnome desktop is in most ways better from a design and usability standpoint than Windows Vista.