I suspect the number of non-fractional owners worldwide, who still control their keys, is less than 5 million.
It certainly seems that way... and that's why I'm not necessarily on board the, "this is tulips in the Netherlands in 1600s, GET OUT NOW!!! AHHHH!" train of doom and gloom.
If the whales are fully committed to playing the long game with Bitcoin, this could go on for quite some time due to the ability to divide Bitcoin into such tiny fractions.
The number of users/vendors looking to do business in full coins is doing to dwindle (if it hasn't already), but the number of users who just want to buy .000001 or less coins is pretty much infinite.
It also seems that the majority of the "whales" have two things common:
1) They are invested in not just becoming rich, but also in seeing Bitcoin become universally accepted.
2) They have very deep pockets which gives them unprecedented ability to manipulate the market... which isn't anywhere near as fluid/open/organic as it appears on paper due to the things I pointed out in my earlier post.
While I'm not in any way suggesting these whales are being altruistic (I'm sure every one of them has already hedged their initial investment and regardless of what happens will walk away a winner), I also don't think that they are your typical "rational" investors who are going to pump and dump.
A rational investor would have flipped their $11,000,000 investment that is now worth over a billion dollars by now. They would have done it long ago if their end game was just to become filthy rich. The fact that the Winklevoss' and Nakamoto's of the world aren't dumping leads me to believe that they are trying to go out of their way to see Bitcoin succeed in what most of us would view as an irrational way.
If the entities that own 75% or so of the industry are all on board to continuing the charade... it's possible to see sustained "growth" for years to come.
It's also possible that one of the early adopters decides to dump everything and buy their own island(s), and Bitcoin plummets tomorrow. If that was going to happen though... one could argue it would have happened a few weeks ago when the exponential increases were being reported almost hourly ($10000 to 12000 to 17000 in a span of days/hours, instead of weeks/year). The fact that it didn't plummet at that point moves it out of the "beanie baby/tulips in Netherland" territory and into something different.
What that ultimately is? I'm not sure, and I don't think anyone else does either.