Apple releases new versions of their products on a certain cycle like most vendors, however, they've realized that they can't go obsoleting the computers based purely on marketing and forcing consumers to upgrade since the computers tend to cost quite a lot compared to other vendors..
However, they seem to deem the iPods, iPhones and iPads in a different light and care less about obsoleting previous generations JUST to make the newer version more appealing.
I mean, at the end of day, if you look at the iPhone 4 and iPhone 4S. The big differentiation is that 4S has Siri, 4 does not. I am totally skeptical of the reasoning that the iPhone 4 hardware can't support that. Then on iOS 6, they opted to not support turn-by-turn direction and other cool features in Maps on the iPhone 4, just the 4S. But the Google Maps app on my iPhone 4 has no problem handling the turn-by-turn directions..so I call BS on that..
Now I realize that they'd have people up in arms if they allowed the latest iOS to function on the original iPhone since the only way they can support that is with limited/curtailed functionality and that's going to **** people off. Allow full functionality and the lack of performance will **** people off too. Also, now they have to create a group within the iOS development team just to cut functionality with each version of iOS to make it work on previous generations of the iDevices..so I get all that..and I think MOST reasonable people will realize that iOS 6 will just not be good on the original iPhone..
But cutting of newer hardware to force Marketing obsolescence is just annoying..