I don't understand Tesla's stock price and valuation. TSLA is trading at about $175/share right now, with a market cap of $21 billion.
So the market is valuing Tesla at about half the value of GM ($52B), and 1.5x the value of Porsche ($13B)
Based on what?
Tesla is emphatically not Apple. Apple rose to become a top 3 player in mobile phones, the top player in tablet computers, and the top player in MP3 gadgets. Apple sells millions of units, and makes money on hardware, software, service, and content.
Tesla has to make money selling cars--a very highly regulated, capital intensive business. Tesla isn't able to sell direct to consumers in all states of the U.S.
Let's compare Tesla to Porsche.
2013 Sales (1st 2 quarters)
Porsche: ~$10 billion
Tesla: ~$1 billion
The stock buyers apparently think that Tesla is a growth company, and are pricing in the expectation that it will grow to something quite a bit more profitable than Porsche. In 2012, Porsche recorded a profit of $2.7 billion. To reach those kinds of results, Tesla has to sell approximately 125,000 cars a year (at $80,000 each) if they are making a similar margin to Porsche. If Tesla goes down to an average price of $50,000/car, they have to sell about 200,000 cars/year.
That's about 8x their current capacity of 500 cars / week (25,000/year).
So, the market seems to think that within a few years, Tesla will be able to open several new plants, and successfully increase their sales and distribution network to rival Porsche, while moving downmarket enough to drive higher volumes.
I am doubtful.