For those with P85+, I understand your frustration - you bought the highest performance model, paid a premium, waited years for delivery, and now within months there is a better performing model. That sucks.
For those worried about resale value, I am not so sure. I plan to keep my car for 5 to 7 years, and in that time there will probably be D, D+, triple-D+, Model X with 7 seats, Model 3 at half the price, etc, etc. I can't see how D or no D on a 2014 Model S will be immensely relevant in 5 years time.
And finally, for those suggesting Tesla do it some other way - how? Just not innovate and improve the car (remember it is 2 years old in USA already)? Perhaps intentionally delay the introduction of new innovations? I really don't see any feasible way for Tesla to satisfy existing customers when they release a new better product.
I've seen comparisons against the phone industry. Well, I just bought a new smartphone, and Apple didn't give me anything back for the one I already owned, and they didn't offer me a flash or cpu hardware upgrade either.