N.B.: This review was of Minecraft in its earliest outing; see here for a more recent (and favorable) take on the game
Back in the day, I entered Habitat and played around with it. And I remember Chip Morningstar telling me that it "wasn't just a game," and thinking "Too bad! It could be a pretty good game!" That is, if you bolted on some, you know, actual gameplay. Something to do. An objective.