This article is just plain wrong on a number of points. They are wildly extrapolating from a tweet. "Ending range anxiety" could be anything from performance improvements, to more accurate routing, to a better system for finding charging points.

"Tesla similarly upgraded its Roadster electric cars last year, expanding their range to almost 400 miles between charges via an over-the-air update"

While that would be incredible if true, it is not. They have announced the availability of a physical battery upgrade for the Roadster that includes a complete battery swap, drive train improvements, and other stuff derived from the Model S research.

This is ridiculous, CNN aren't even reading their own linked articles.