Apple has said that it has not any plans to implement Siri into any other iOS devices besides the iPhone 4S. Apple confirmed it today in an email to developer Michael Steeber.
Engineering has provided the following feedback regarding this issue:Siri only works on iPhone 4S and we currently have no plans to support older devices.
That doesn’t mean however that developers won’t continue to work on building Siri for later iOS device — like the iPhone 4 and 3GS. Curious to see how it works on an iPhone 4?
Here’s a screenshot for the email :