Having now played several games of Small World, I believe that Days of Wonder has another hit. With the combination of Races and Powers, the variety in each game is astounding; a race may be looked over one game (Hill Humans? What am I supposed to do with those...?), only to find its combination with another power exactly what a player needs in another game (Berserk Humans! You're dead now!).
The rulebook is clearly written, and the game also scales extremely well--it actually comes with two double-sided boards, each marked with a number 2, 3, 4 or 5, to denote which board to use depending on the number of players.
Presentation: 8 of 10 (only marked down for lack of clarity of in-decline chits)
Difficulty: 4 of 10 (most people should be able to play this game with little or no help)