Well, here I am again, after surviving Level 1.
The way Madness as built using glowstone and glass to form a spiral staircase really looks nice. Also, the fact that the staircase was spiral and that I was falling down (as in down) confused me and screwed up my usual Minecraft reaction. All in all, a great beginning level.
In one of the water holes you can land in at the end, there is a chest. Open it, and there's a diamond. Just take it. You don't need them to win the game. Just take it.
I'm ready for Level 2 (Fall) now.
PS: Oh, and I also like the Dropper's checkpoint system, in which retracted pistons reveal the hallway to the first drop. Very nice system. That way, I can visit my pet pigs. (Bigre included 9 Spawn Pigs in a chest at the beginning. I think it's for food. But I like pigs.)