writes "Tesla won't reveal its production figures every quarter, but it has now likely built about 50,000 all-electric Model S luxury sport sedans. Unlike other automakers, Tesla doesn't group its changes to a model year, rather it makes running changes to cars whenever updates are tested, validated, and ready to roll out. Which begs the question, are model year 2012 Model S sedans already outdated? The answer is it depends how you look at it. From a powertrain perspective, no. There are still two battery-size options and the shape is still the same. But under the surface of the car there are a surprisingly number of updates and new options. Not including software changes which there are dozens of and are pushed to the car, changes range from power folding mirrors and a new cold-weather package (which cannot be retrofitted) to a new ultra-high-fidelity sound package and three-zone, three-mode rear seat heaters. It's worth noting that none of these are mandatory changes--there are merely options that have been added to the roster of available equipment."