This sounds more like wishful thinking on your part than anything based in reality.
I'm not claiming to be sitting on a complete set of statistics here, there simply is no way of knowing for sure, we can only make assumptions and more or less educated guesses.
Sure, some users undoubtedly have multiple MorphOS systems registered (I have 2 myself), but there should also be a lot of people having only ONE registration. Even if the MorphOS hardware is very cheap, MorphOS registrations aren't exactly for free. New users in recent years (that got themselves a, say, PowerMac or Mac Mini as their first MorphOS system) probably won't see a reason to register a second computer of similar kind. This may change when PowerBook support is introduced with the release of MorphOS 3.0, it will be interesting to see how the registration graph develops after that. And you must remember that MorphOS is perfectly usable (without any limitations whatsoever) without a registration, at least for 30 minutes at a time...

There seems to be some sort of general consensus that "a fair number of users" would currently be obtained by dividing the registrations with 2, and I agree, I think it's a fair assumption. This would give around
700 MorphOS users, which is a pretty decent number actually!

Timberwolf for OS4 has been downloaded
770 times at the moment. I *sincerely doubt* that any active OS4 user haven't downloaded this piece of software by now, given all the hype, all the attention, and the poor browser situation on the OS4 platform in general. It's "the holy grail" in the OS4 world. I think it's fair to assume that close to 100% of all active OS4 users has downloaded Timberwolf now, when almost a month has passed after its release. But don't forget that many active OS4 users today have multiple systems as well, this is not a phenomenon limited to MorphOS. Multiple downloads comes from this. And as has been pointed out, there might be some problems downloading SW using some of the OS4 browsers, resulting in multiple downloads per user simply because of troubles/errors, people will DL it again after re-installing their computer, etc. And (as we have seen in the past), you can't rule out that some people actually makes multiple downloads simply to make a "statement" through these kinds of statistics (especially after numbers have been
publicly discussed).
Anyway, I think it's a fair assumption to divide that number by *at least* 2 as well, which gives a picture of about half the amount of active OS4 users compared to MorphOS users, meaning some
300-350 people, possibly less.
I don't want to belittle AROS in any way, but MorphOS and OS4 plays in a completely different league. I sincerely believe that very few people (other than the developers and some hardcore enthusiasts, counted in a two-digit number in total) *actually uses it* actively, at least in a comparable manner as MorphOS and OS4 is being used. I think people may download it (various "distros") from time to time out of curiosity, to check out how far it has come since the last time they checked it out.
About 700 active MorphOS users would mean 2x the amount of about 300 active OS4 users coupled with some 50 active AROS users.
But again, your guess is as good as mine...