Tesla is striving to build:
- Electric cars that are attractive in looks and performance, are safe, have a good range and are not expensive
- A world-wide system for charging relatively fast
Tesla is building this future very fast, but they are not there yet.
The biggest work that still needs to be done is improving the battery technology.
Attractive and relatively cheap electric cars are the future
Many car manufacturers are finding ways to build higher MPG vehicles. If Tesla is successful with their current research in designing a more affordable car (their current electrical car goes for over $70,000) that the middle class can go to, they can pave the way car consumers go about buying cars. Most importantly, their approach for not using much gasoline, if at all really, will be revolutionary; other companies are finding ways to build electrical cars only (Nissan with their Leaf) and slowly more of them are popping in the market. However, Tesla aims at removing gasoline from the equation and I believe that they're gaining speed and heading in the right direction. Once they tap into the middle-class market it will be very difficult to compete against.
Sometime in the near future, there would have further development of hydrogen powered automobiles, which are environmentally the best of both options. I believe the reason Tesla is currently succeeding is because of all the hype they had created before releasing the Model S to the public. The roadster certainly didn't catch on, or at least outside the united states.