Developer Steve Troughton-Smith has hacked Siri, the artificially intelligent voice control system on iPhone 4S to run on last year's iPhone 4. An initial hiccup, GPU support, has already been overcome. Another hiccup, Apple's servers not responding to queries from Siri running on iPhone 4, is still and issue.
Troughton-Smith also suggests it could theoretically be possible to hook the Siri front end into Microsoft's TellMe, or Google's servers instead.
If Troughton-Smith could get Siri running on an iPhone 4's single core Apple A4 processor, it probably makes you wonder why Apple didn't include it in iOS 5 for iPhone 4. Apple, of course, famously didn't bring video recording to iPhone 3G when Jailbreakers had it running. It's either a feature they want to keep exclusive to iPhone 4S for now, or something Apple's perfectionistic nature won't allow them to do if it' s not 100% smooth and performant. Or both.
Stellar work by Troughton-Smith, check out his Twitter feed, below, for more.