Re: How many aikidoka?
Interesting question; I haven't read the organizations thread so I don't know the discussion there.
A couple of quick google searches came up the number 192 for the number of countries in the world. I don't know if I would hazard a guess that Aikido is practiced in all of them, but certainly in most of them I would think.
With that number of countries in mind I would then venture to speculate that the number of Aikidoka worldwide would certainly be in the hundreds of thousands, if not millions.