The notion that somehow consumers aren't price sensitive is nonsensical, unless one is part of the super rich. If that's the case, then what price an average consumer pays has no bearing.
The gist is here is that in prior years, a consumer didn't have a choice, other than to pay the contract price. Until now, ATT had never before offered an off-contract price. Moreover, in the past, even if you were out of contract, it made no sense not to upgrade, since there was no discount for not doing so. Hence, everyone was forced to upgrade at 2 years.
Without contracts (VZN still charges the same regardless) on ATT and T-Mobile, the consumer now has an incentive to forgo the upgrade, bring a phone from elsewhere, or purchase outright with the full transparency of a respective phone's retail price.
None of this suggests Apple can't continue selling phones at $650 retail price. The implication is that once prices (perceived or otherwise) goes up, then demand must necessarily go down. Simple supply vs. demand. Of course, if Apple were an inelastic good (such as medical care), where the forces of supply and demand no longer apply, they'd be a Monopoly. Remember MSFT 10 years ago? They were close.
In my view, future trends will depend exclusively on iPhone 6. If Apple makes a product, which it has many times in the past, that completely out classes the competition, then they can move the goal posts, and command the $650 - $800 range for their new phones, with all the rest plummeting in price.
What happens will depend on iPhone 6. And, should iPhone 6 redefine the industry, you'll see AAPL shoot through the roof, since we've all priced in slower growth with decreasing profit margins.
Personally, I hope iPhone 6 will shock the world with innovation. Not because I'm partial to Apple, but because I like the world that's created by competition and practical innovation.
If Apple can do this, then iPhone 6 at $650 will sell like hotcakes.