If that is the case, why not DRop the 3GS, or the iPhone 4, because it has a SLOWER processor than the ipad
They provide some updates for the 3GS but almost all new features are disabled for it. They are trying to tell you to upgrade to something that gets new features. The iPhone 4 does get some features but the newest iPhone the 4S is the only Phone That Gets all the features.
I'm sure they'd drop the 3GS if carriers weren't selling them right now. Other else than that, I guess Apple just wanted to drop non-retina devices.
http://www.ifans.com/forums/threads/halolordkiller3s-itunes-content-giveaway.376657/ I was giving away Instapaper.
How much power the feature requires. For example, if facetime over 3g is exactly the same facetime without the 3g restriction, then there may not be an issue apart from removing the restriction.