Before there are wrong conlusions based on the map stats ill try to explain the stats, based on my oppinion:
Cataract: very good map, first beta map released. Promotes teamplay and has a somewhat easy structure that also allows for advanced plays and tactics. No suprise to see it on #1.
Crucible: Its not a huge suprise that smaller maps are on top of the list given the number of connection problems. Also this is the the only 2v2 map. I strongly dislike this map because the game only has one lane and once you push past a certain point its over, sure there are tricks to warping out, but overall this map is pretty boring. two lanes that are somewhat close would be ideal for a 2v2 map, although 2v2 is not how demigod should be played anyhow...
Exile: Solid map.
Leviathan: Solid
mandala: the game differs on this map because of its vastness. Quite suprised to find it up there but i guess once you get enough players it can be somewhat fun.
Prison: An interesting map that differs the game because of its lack of defensive towers which is a huge deal in early game. It promotes diffrent play while being perfect for 3v3, a very good map.
Brothers: This is probably the worst map of all, it just seems like you dont get any money on this map, thus less items, less deviation, less fun.
Zigurat: No idea why this is at the bottom, personally i think its the best or at least top 3. A somewhat larger income makes it very interesting (diverse gear=fun). I guess it being a 5v5 map is somewhat misleading as its best played 3v3 due to the lanes being close by, the portals are well placed off the beaten pass and allow for pressure from more sides. For anyone reading this, try it as a 3v3 map and you will be suprised how much fun it is.