I've thought a lot about this recently; for various systems. How many players/collectors there are for certain niche systems must be a very finite number. Are there more than a few hundred CD-i gamers in the world currently? Or Virtual boy? To loosely define this; i would say anyone that has a working system, a few games, and hooks it up to play it at least once a year or so. And maybe this kind of person would post on online occasionally about the system, buy the odd game off eBay or an occasional homebrew were once to become available.
So i ask this about the Jag. It's a hard number to estimate. I'm guessing if a few hundred thousand were make, maybe somewhere between 800-2500 active users still exist in the wild? Not everyone will buy the latest homebrew for example, but if 350 do, and you get a 10% purchase rate, then maybe as high as 3500? But then you will have the folks that don't go on forums, aren't buying homebrews etc. but just have their original collection in the basement somewhere that they play a few times a year.
It's impossible to know for sure of course; but i wonder what everyones professional opinion is on this one. Maybe i'm way off; maybe there are 10k jaguar players out there in Japan, NA, and Europe. Looking forward to seeing peoples thoughts on this.