All the other car makers are currently mostly in the 75- to 100-mile range for their all-electric cars. For longer-range cars, they use smaller batteries in combination with a gasoline (e.g., Chevrolet Volt or BMW i3) or diesel (e.g., Volvo V70 D6) generator.
The argument as to what's a better long-distance driving solution -- all-electric or range-extender -- will continue to rage for years. Reflective of this, both solutions will also likely thrive in the market for at least another five to eight years, at a minimum for cost reasons.
At some point between 2016 and 2019, however, multiple Tesla competitors will be delivering all-electric cars with ranges from 200 to 300 miles. Of course, you may say that by then Tesla will have moved the competitive needle to 300 to 400 miles.
Perhaps. But then again, perhaps Tesla's competitors will also have 300- to 400-mile, all-electric cars by 2019 or 2020. The precise number there is not important for this discussion, as you will see below.
Regardless of which company -- Tesla and/or its competitors -- will try to deliver large, luxurious, all-electric cars with well over 300 miles of range, those cars will be expensive and add a lot of weight. There simply comes a point when you need more heavy batteries to transport around the additional heavy batteries. Weight and cost become prohibitive, except perhaps in an electric Rolls-Royce.