Each week Ross Rubin contributes Switched On, a column about consumer technology.
This week saw significant and contrasting twists for the legacies of two operating systems that had their roots in the heyday of the PDA. HP revealed that it is killing off the Palm brand, and Nokia announced that -- while it would continue to "harvest" less capable versions of the Symbian operating system on its basic handsets -- it would shift away from the operating system in its smartphones in favor of Windows Phone 7. In some ways, the demise of
