Switched On: As Siri gets serious

Nearly 15 years passed between Apple's first foray into handheld electronics -- the Newton MessagePad -- and the far more successful iPhone. But while phones have replaced PDAs for all intents and purposes, few if any have tried to be what Newton really aspired to -- an intelligent assistant that would seamlessly blend into your life. That has changed with Siri, the standout feature of iOS 5 on the iPhone 4S, which could aptly be described as a "personal digital assistant" if there weren't so much baggage tied to that term.

Siri is far more than parlor entertainment or a simple leapfrogging the voice control support in Android and Windows Phone. At the other end of the potential spectrum, Siri may not be a new platform in itself (although at this point Apple has somewhat sandboxed the experience). In any case, though, Siri certainly paves the way for voice as an important component for a rich multi-input digital experience. It steps toward the life-management set of functionality that the bow-tied agent immortalized in Apple's 1987 Knowledge Navigator video could achieve.