This has gone from 'wow, that's a neat-looking thing' to something a whole lot bigger.
I did notice, a day or two ago, that Octopath Traveller was remarkably difficult to find. I hadn't actually walked into a games store intent on picking up a copy, mercifully - I was just passing by. But, boy, those sold out signs were everywhere.
It would seem, however, that 'everywhere' isn't just hyperbole - it's really difficult to get a physical copy of this game! So much so that Square Enix has issued an apology of sorts over Twitter (along with a reminder that if you want something physical, you can probably still buy a download card at a convenience store... which kind of defeats the point) to fans.
This doesn't seem to be just Japan, either. A quick search shows physical copies of Octopath Traveler to be sold out on both the U.S. and Australian branches of Amazon. So, if you see a copy out in the wild and want to give it a spin, maybe grab it right away?
In any case, it seems Square Enix grossly underestimated demand for their visually stroking throwback. Hopefully this will encourage a little more... adventurousness going forward?