Microsoft CEO Steve Ballmer today said that a touch-specific version of Office will, at some point, reach the iPad.It was the first time that a top-level Microsoft executive publicly promised that the lucrative Office franchise would run as a native app on Apple's iPad.Ballmer's remarks were made during his time on stage Tuesday at the Gartner Symposium, the research firm's annual IT conference when he was questioned by Gartner analyst David Cearley about Office plans."Word, PowerPoint and Excel are all authoring tools," said Ballmer. "They are optimized for use with keyboards and mice. The last time I checked, the iPad didn't have a paradigm for keyboard or mice. iPad will be picked up when we do what I would call not just a touch-enabled, but a touch-first user interface [for Office]. That is in progressfor both Windows 8 and other platforms."When Cearley lightl