Both Nokia and RIM were vanquished because they failed to invest in their future - the big three are investing, and buying technology companies to fill in what doesnt make sense to build themselves.
In this case, I see no big paradigm shift that would presuppose me that any of the big global auto manufacturers would go away.
Building good cars, is a game of logistics and supply chain, something Tesla is largely still learning - the thing about building a good electric car is, it only changes one aspect of an otherwise concept, and you can buy the technology you need for that.
RIM, Nortel and Nokia, are not good example cases, because they didnt loose on their ability to manufacture shit - and Tesla likely will.
I wont bet against him either - but I wont bet on him either - and thats where I sit. I wish him all the best, but history has seen others try, and fail.