What is Siri?
- Is it really only for voice control?
- Don't we already have one of those on the previous iPhones?
Think of Siri as your personal assistant. It listens to your commands, learns from your tasks & contacts & replies to voice commands.
Well, they're no longer available for the previous iPhone as the app has been taken down.
The new, improved Siri was developed after it's acquisition by Apple, so I'm pretty sure they would have added their Patented SecretSauce(tm) and in typical Apple style, the details are a secret.