Let me back up. First of all, there are no
requirements to be considered. Just existing is enough.
Though active development is pretty much required for any kind of extended stay on the list (see AVS and Sapphire Claw).
But this is a hype list, after all, and not knowing when or even if a game will ever reach market tends to put a crimp in people's enthusiasm after a while, and that's where publishing factors in. Self-publishing is just fine. But if there's no publisher at all, then you risk situations like Boyz Don't Cry, which looked really intriguing, and even made the list for a while, and then never panned out (in English, anyway). So we'd rather avoid that if it's a toss-up between games of equal quality.