Tesla sure knows how to generate buzz. Speculation was rife over what it’s mysterious “D” announcement, tweeted to a breathless world, would turn out to be.
 

The most common guess, which turned out to be true, was that the “D” stood for “drive,” and that Tesla would unveil an all-wheel-drive system for the Model S (piggybacking on technology developed for the Model X). That made sense, and was egged on by a fairly clear spy photo of a putative Model S P85D. The Daily Mail reported that the car “could rival a Bugatti,” which is true enough—the P85D goes to 60 mph in 3.2 seconds.
 
But Steve Burns, CEO of Cincinatti’s AMP Electric Vehicles, predicted that the “D” was the Roman numeral 500, and that Tesla would announce a 500-mile-range car. Look at the timing, he said. The cryptic tweet came “just hours after GM held a demonstration at the Milford Proving grounds, telling investors that GM plans on delivering an all electric Chevy, with a 200 mile range between charges, for about $30,000,” Burns said.

Once we found out what it costs, we developed our own theory--that the "D" stands for the dough you'll be doling out to own one of these.
 
Since that’s the approximate goal of the Model 3, in this scenario, Tesla responded by saying, “About time to unveil the D and something else.” Burns thought that Tesla’s gigafactory is somehow paving the way to a 500-mile car.
 

The something else turned out to be Autopilot. What Business Insider called “cruise control on steroids.” It reads speed limit signs and adjusts, and makes turns on its own. No, it’s not the driverless car, but as we’ve predicted it’s going to creep up on us feature by feature.

Anyone remember when Dean Kamen unveiled the Segway in 2001, with enough hot air to float the Goodyear blimp? The claim was that it would change transportation forever, so the subsequent gyroscopically balanced scooter was a bit of a letdown.
 

So too is an all-wheel-drive Model S, maybe with autopilot features. But CNN reported that CEO Elon Musk’s tweet added $2 billion in market value to the electric car company. Kudos to InsideEVs.com for having approximately the right idea.  

Here's a look at the Model S P85D, and the Autopilot features, on video: