China ready to take off?
After quietly opening its first store in Beijing earlier this year, Tesla says that the gallery has become the company's largest and most active in the world.
While Tesla won't reveal how many orders it's booked in China, Musk says demand is strong.
"Based on current trends it seems unlikely that we will be able to satisfy demand in China this year," Musk told analysts.
Later this Spring he'll travel to China for the first delivery of a Model S to a Chinese customer. As the year goes on, Tesla will not only expand sales in China, but start developing a Supercharger network for that country.
'Giga factory' expanding production
While it may not garner the headlines that will push consumers to buy a Model S, development of the Tesla "giga factory" is a major story for the company in 2014.
The company needs a greater supply of lithium-ion battery cells and battery technology, so Tesla vehicles can deliver greater power at a lower cost. That's why Tesla is partnering with other companies to build its giga factory.
"Very shortly, we will be ready to share more information about the Tesla giga factory. This will allow us to achieve a major reduction in the cost of our battery packs and accelerate the pace of battery innovation," Musk wrote in the investor letter.
Where this new facility will be built and when it will begin producing lithium-ion cells and battery packs is still not clear.
Model X building momentum
Meanwhile, the focus will shift to Tesla's next car, the Model X SUV (sports utility vehicle) during 2014.
Sales will start early next year, but already Tesla is seeing heavy interest in the Model X.
"Even though there is zero marketing for the Model X, it is like if you are going fishing and fish are jumping in the boat," Musk told analysts. "We are not actually trying to sell the Model X at all, but demand seems to be remarkably high."
Eventually, Musk expect Model X sales to exceed sales of the Model S.
—By CNBC's Phil LeBeau. Follow him on Twitter
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