The guy launches rockets and builds electric sports cars ... I tend to think he has a plan. Allowing the speculation to persist might improve that plan but I suspect it was viable on it's own (and perhaps the waiting period was simply to allow some small scale testing to occur).

To be honest that is what my money was originally on.. that or this just being some sort of self-constructed mythology for himself, sort of like free wirelessly transmitted power was for Tesla perhaps (though more 'intentionally' and less 'mistakenly/delusionally').

As time goes on he keeps getting more and more specific with his deadline for going public though. First it was "eventually", then it was "sometime after Tesla is profitable", then it was "sometime later this year", now we've actually got a date to look forward to. I now think that he actually is thinking of something.

You know... this remark got me thinking, and it turns we've been here before as a society, with remarkably similar technology (superficially, at least) and technologists hyping it up a little. Look up Beach Pneumatic Transit - the first New York City subway, in a tube, powered by compressed air. Which is kind of cool: http://en.wikipedia.org/wiki/Beach_Pneumatic_Transit

"A tube, a car, a revolving fan! Little more is required. The ponderous locomotive, with its various appurtenances, is dispensed with, and the light aerial fluid that we breathe is the substituted motor!" -- http://www.columbia.edu/~brennan/beach/chapter2.html

Trains in tubes and promises of dramatic changes in the way people think of transportation! People thought they would be building tubes all over the countryside to move trains around... and then they went and invented the electric-multiple-unit subway train which took off instead. :P

Better luck this time?

Or even if he does have a design planned, he might consider "creating other usable designs" as a deliberate side effect of stirring up speculation. He seems to be motivated by saving the world in general more than personally making a lot of money.

I had that thought too, but I do think he has a plan. I don't think he'd risk so much of his reputation by pulling a stunt like that.