A subsidiary question, and one which interests me, is the size of it. A figure of 10,000-20,000 is given as a guess, but there is of course no way of knowing if that is at all accurate or not. Apart from anything else it all depends on the definition you want to use; does being "into OSR stuff" mean you have bought a product? That you read 3+ blogs that are about "OSR stuff"? Impossible to say and depends on arbitrary decisions of the person making the calculation. So in a sense it is a pointless question to ask.
But late modernity is characterised by nothing more than misleading and foolish attempts at quantifying phenomena that can't really be quantified, so let's not let that stop us.
I am going to define "into OSR stuff" as "having played LotFP, DCC, Swords & Wizardry or LL more than three times, and/or having played a TSR D&D variant in the last year more than three times, having abandoned it for a period of more than 5 years".
How many people are actively "into OSR stuff" on the internet, first of all?
The big OSR luminaries (Zak S, James Raggi, Kevin Crawford, Patrick S, etc.) tend to have in the region of 1,000-4,000 followers on G+. The OSR community has 4,966 members at the most recent count. Swords & Wizardry 1,572. Labyrinth Lord 1,439. There is likely to be huge overlaps between these groups, (although of course not everybody is going to be in one) so I would put an upper limit of around 5-6,000 people active on G+ who are into OSR stuff.
G+ is not the be-all and end-all, of course. It is used disproportionately highly by gamers in comparison to other demographics (who barely ever even think of it at all), and it is hugely influential amongst OSR types because it seems to have a way of sucking them in like the proverbial flies to
What about forums? Dragonsfoot, probably the biggest, has 10,372 members as of this date. There can be expected to be some overlap with G+, though my general sense is not a huge amount - they seem like pretty different crowds. And many of those people are not going to be active. Throw in a few more thousand potentials from odd74 and K&KA put together - again, some of whom will also use Dragonsfoot and/or G+ - and we can suck a finger and stick it in the air and say that this increases the scope to around 14,000 people on the internet who are into OSR stuff. That is, around 5-6,000 on G+, and around 8,000 more on grognardish forums once you take into account overlaps with G+ usage.
You can then throw in 1,127 members of the LotFP forum (again, big overlaps with G+, Dragonsfoot, etc.), and other dribs and drabs here and there (around 100-ish members on the S&W forum, for instance). Then it gets yet more nebulous when it comes to blog readership. It feels rather like pulling my pants down in the middle of the street to give you a glimpse behind the curtain in this way, but my readership generally plateaus at around 1,500-2,000 per post. I would never suggest that my blog is big - middling really when compared to some others - so I suspect there are some out there that get 5,000, 10,000 even. But again, there will be a lot of overlap with G+ and forum usage. Sucking a different finger and sticking it into the air, let's say the scope increases to something like 17,000 if you include people who exclusively read the blogs and don't go on G+ or forums.
You can then add in people who are into RPG stuff online exclusively through the use of reddit, Facebook, Twitter, Tumblr, etc., but I think this group must be tiny - most of people who actively use other social media to discuss OSR games will be included in the above groupings.
The number of people who are into OSR stuff on the internet is not going to reflect the true total, though, because as we all know it is usually only DMs who go online and discuss games, buy game products, and so on, and DMs are always going to be a minority of gamers. Maybe a ratio of 1 DM to 3 players? Making the scope of people who are "into OSR stuff" by my definition about 68,000?
- It's all bollocks because it's based on semi-informed guesswork, but we know that anyway.
- It's English-language specific. There will be loads of other-language forums and blogs where people are into OSR stuff.
- The information is basically valueless, because it doesn't affect anything.
- You will have your own definition of "being into OSR stuff".
Still, 68,000 worldwide in the English language is my rough guess, so there.