Actually I suspect there are "real" people behind the sign-ups, but they still constitute inauthentic site traffic, and so my first blog post is a heads-up to existing site members:
I've seen a flood of member sign-ups on the site this morning, all of them from Gmail addresses that begin with "hello-world," as you can see here:
My best guess is that the email addresses are all "burner" accounts created for the purpose of an ad scam. I recently started advertising the site with Google Ads in an attempt to drum up some business for the summer (especially in writing skills tutorials; if you know somebody who might want a summer tutor for upper high school levels/college prep, SEND THEM TO MEEEEEE!!!!!) and the way the setup works is that Google shows your ad in search results but also on third-party "partner" websites, and you (or, in this case, I; the ad buyer) pay not when your ad is shown but when your ad is clicked.
This means that getting eyeballs is cheap (and potentially a good value for the money; as Google points out, "impressions," which is what they call people seeing your ad, improve brand recognition and the chance that somebody who sees them will think of you later, the next time they need whatever it is you are selling), whereas clicks (somebody tapping the ad to visit my website) costs money –– not a whole lot of money, because I'm cheap, but more than I can afford if the clicks aren't bringing people who are legitimately interested in what I'm up to over here.
It ALSO means that the "partner" websites, who earn revenue from letting Google place ads on their pages have a lot of incentive to make placing ads there look valuable ... by, for instance, showing Google that ads placed on their pages have a high click rate (thereby generating revenue for Google, which isn't charging me for showing my ad but DOES charge me whenever it gets a click).
I don't know how Google currently rewards conversions from partner website clicks, but it's a good bet they do (because it makes good business sense). A conversion is any time somebody clicks the ad to follow your link and then takes another action on the site, like visiting a sub-page or viewing "more info" on a product for purchase.
You can choose, in the ad setup, what you would like your particular site conversion to be –– and I actually didn't pick "increase site memberships" (I wanted people to go scope out my pricing plans), but that's a common goal for a lot of sites that offer memberships, and so generating as many signups as possible within a short window makes a lot of sense as a way of demonstrating to Google that placing ads on your own site is a good idea that should be rewarded with a cut of the profits ... which, again, come from charging my broke ass.
So far, none of these new "members" has tried to post to the forums or share any files or otherwise "do stuff" on the site (well, why would they? ... they did what they came for), and I have both suspended my Google advertising and temporarily reset site permissions so that I have to manually approve new members. I've seen about three or four new signup attempts since I suspended my ads, but I figure those are just people who got hired for this shady "click as many ads as you can" scheme several hours ago and are still working their way through their open browser tabs. I expect the trickle to dry up, probably before tonight.
In the meantime:
Don't accept Member Chats and especially don't download files or click any links from anybody you don't already know.
Most of you already know one another to some degree, but if you would like to get better acquainted, we have a very nice Member's Forum space for doing just that.
Cheers to an otherwise great weekend ... and if you have any questions or any of the newbie quasi-bots give you trouble, just let me know.