The game's not even completed yet and it's hit 1,000,000 members! I remember Minecraft back in August when my friend told me about it! So, it seems with Minecraft's rising popularity -- sales are going through the roof. The game is selling thousands per day! Notch has made well over a million in currency. Except... swedish taxes and PayPal freezing (then unfreezing) his account.
It seems that with Minecraft's success, Notch ALSO has made his success. He's been in talks with lawyers and companies. He's actually trying to get an office to setup his company! He's already hired someone but it will be all-out on Minecraft. After he has everything in Minecraft that he wants -- he's "finished". I don't think he will be for a long time. A large userbase is behind it and the game isn't completed yet.
But I think I speak for every Minecraft player when I say "Congratulations on 1,000,000 members" and "thanks for your hard work".