I doubt whether Tesla will eventually become a major player on its own in the global motor vehicle industry – but time will tell.
However, where I believe Tesla may become a major player is the energy industry – with their home battery technology.
If I was an executive of an energy utility, I would be very concerned by the advent of home batteries, such as the Tesla Powerwall ( see link below to Mashable article). The home battery makes Solar a real option for households and small businesses, particularly in places like Australia. It means that a lot of households can disconnect themselves from the grid or become a net supplier rather than a net consumer.
Often, an innovation or invention’s greatest impact is not in an industry which it was first designed for – I think that is very likely in Tesla’s case
http://mashable.com/2016/01/28/first-tesla-powerwall/#cvYDGGmvZgq1