I don't expect my car until early February, but having spent some time reading this thread and others related to winter driving, I have some thoughts. I live in Vermont where driving in snow is a fact of life.
First, many owners appear to have inflated expectations of the Model S as a winter car. Let's be realistic. It's a relatively heavy RWD car, not an SUV. I would expect its winter driving capability to be in line with a BMW 7 series or a Mercedes 2WD E class car -- perhaps slightly better given the Tesla's superior weight distribution. The value of a good set of snow tires is not to be underestimated. (I plan to go with Dunlop SP Winter Sport 3D.) But even then, the Model S may not be able to handle every icy hill you throw at it. I plan to keep my Audi around for those particularly challenging winter days. But for 90% of the winter, I expect the Model S will do just fine.
Secondly, it has become clear that there are a few issues the factory needs to address ASAP: the window fogging problem on the driver's side of the car, the Traction Control issue, and the side window icing:
The fogging problem sounds as if it can be fixed with a minor re-design of the duct work behind the dashboard. (Hopefully, that's something the service centers will be able to handle as an upgrade.) It is surprising that Tesla's winter testing did not expose the fogging problem. I think Tesla would benefit by building an environmental test chamber at the factory to test their cars in all sorts of temperature and humidity conditions, not just those found in Minnesota during one short period. Here in the Northeast it is more humid in the wintertime. That's why the fogging problem is more noticeable in this part of the country. (Apparently, a good temporary fix is to simply clean the inside window surfaces with Windex and then treat them with Rain-X.)
As for the traction control issue, I imagine that there's a software fix in the works. Rather than stopping the wheels altogether on ice, the TC ought to allow the wheels to turn slowly until traction is regained. Some sort of audio feedback for the driver (based on the RPM of the rear wheels) would be helpful when TC is active.
The side window freezing to the lower rubber seal is surprising. There are other cars, such as the Mini Cooper, which use the same system for lowering the window slightly when a door is opened. I've driven a Mini through a Vermont winter, always parked it outside, and never had this problem with the windows getting frozen to the rubber seal at the bottom of the glass. This likely has something to do with the type of rubber used for the seal. Again, this sounds like a problem that could fairly easily be upgraded by the service centers.
In the big picture, these are all relatively minor issues, and I expect that Tesla will address them on new as well as existing vehicles. None of these issues would have scared me away from this otherwise extraordinary car.
