They mention the planet in this episode in other Borg episodes. Also, while I enjoy this episode, it was the height of the "Roddenberry's vision", sniffing their own farts again cause "ain't we so great in the 24th century?!?" attitude. Picard was 100% a douchebag when interacting with the 20th century folk. I mean, for such an advanced person, he was a total dick. But, that stuff went away after season 1, thankfully.