Each week Ross Rubin contributes Switched On, a column about consumer technology. The two worlds of Windows 8 -- one: a traditional desktop UI and the other: the touch-optimized Metro UI -- can, at first, seem so different that they contrast like the multiple personalities of Batman's enemy Two-Face. Yet, despite the different appearances, the forthcoming version of Microsoft's venerable operating system is not about absolutes, but optimizations.Conti
