Today Apple has released iOS 5.1 beta 3 for developers. As usual, developers digging in every new iOS release to discover any secrets or hints at the future of iOS devices. Today, the guys over 9to5mac discovered something potentially major, they found Siri Dictation references for iPad.
References appeared in a new section in the keyboard menu called "About Privacy and Dictation". You can see what inside this file in the above screenshot. Actually we don't expect that Apple will release Siri for iPad 2, we highly expect that Siri will port it to iPad 3 next March.
Dictation is not actually functional on the iPad 2 running iOS 5.1 beta 3, so perhaps this will be an iOS 5.1 launch feature for the iPad, or it may be an iPad 3-exclusive feature; a similar process to the iPhone 4S exclusively gaining Siri and Siri Dictation support in iOS 5.0.(via 9to5mac)