Game Informer reached out to Uber, and asked why they would sell an unfinished game at retail. "The real question is, why not?" asked Jon Mavor, one of the game's directors. "After all, they are getting the same game, just earlier. It's a changing world and we hope to continue trying out new and innovative ways to make games."
Planetary Annihilation currently exists in "gamma" state, a post-beta-but-not-quite-full-release stage not often used to describe a game's development. Of course, you could always wait until the game is complete and makes a full launch, which Uber says will happen "when it's done."