A few days ago, evidence surfaced in the latest iOS 5.1 developer beta that Apple could be bringing Siri to the iPad in the near future. The idea sparked some controversy, as a lot of folks don’t see a use for the digital assistant on a tablet.

But what if there’s more to it than that? Cult of Mac has discovered that the Dictation reference everyone is talking about is also evident on the latest iPod touch model. Of course, this could mean nothing. But what if it means everything?

We decided to do some digging of our own, and have discovered that same Dictation evidence on an iPhone 3GS (shown above) running iOS 5.1 beta 3. And while we don’t have an original iPad or iPhone 4 running the new firmware to verify this, we imagine that the reference is on those devices as well.

Given this information, one could assume that Apple is looking to bring at least the Dictation component of Siri to its other iOS products. It’s already been proven that an A5 processor isn’t needed to run the digital assistant, so what would stop Apple from doing this?

Sure, you could say that Apple wants to keep Siri as an iPhone 4S-exclusive feature to propel sales. But what about Dictation? What if it just rolled out the voice-to-text option to other iOS devices? That way it would appease some of the disappointed iOS users that have been left out of all of the Siri excitement, while still keeping the digital assistant exclusive to its latest handset.

Then again, the evidence could also suggest that Apple is looking to bring Siri to other iOS devices in its entirety. You may recall a theory that Apple wanted to introduce Siri on a small scale (limited to iPhone 4S purchasers) at first, while it finished working out all of the kinks. And since it’s been nearly three months since the last documented widespread Siri outage, one could imagine that those wrinkles have been ironed out, leaving Siri ready for prime time.

For the record, there’s not a whole lot of proof supporting any of this outside of the evidence in iOS 5.1. And even then, it’s circumstantial. It’s nothing more than a text file that could have easily been mistakenly pushed out with the latest developer beta. But we think there might be more to it than that.

What do you think? Is Apple looking to open up Siri for other iOS devices?