The rumors are true. Apple is introducing a Siri-based voice control functionality to iOS 5 and the iPhone 4S, called Siri, not Assistant, as reported.
As we’ve previously detailed, Siri will intelligently help you get things done just by asking.
For example, on stage, Apple asks his iPhone “What is the weather alike today?” Siri then responds with “Here is the weather for today” along with a screen showing the weather.
