That didn't keep Sonny Dickson from trying to port Siri onto his iPad. He tweeted a photo earlier today of Siri ported on his iPad. Below is the photo included showing the settings, general and Siri in the iPad settings.
Apple will likely release Siri for the iPhone 4 and iPad 2 after it exits beta later this fall. With the launch of Siri (and the iPhone 4S) on Friday, many have spoken of connection issues with Siri. This is probably due to people trying to get Siri to say funny things, but it is useful too!