I will restrict my comments to three points:
1.) The art and graphics are superb. The sound is quite good.
2.) This is an Age game.
3.) There is plenty of new stuff in the game.
Art:
Ensemble has done something I didn't think was possible... they managed to keep the "real" feeling of the art in Age and Age II even as they made the transition to three dimensions and mythology. The human units move and fight well, look great when they die, and can be told apart based on the graphical representations of techs and inprovements. Myth units look terrific and not cartoony. They look like what you would expect these things to look like if they were real, and are equally convincing when they fight and move.
Sound:
The sound is good, great in places. The sounds surrounding the myth units are terrific, the battle sounds are battle sounds. When there's this much fighting, even the best sounds will become repetitive. The music tracks for the various civs are wonderful (a change of my opinion from the Alpha), and I like the battle music as well as the economic music.
AGE Game:
This is an Age game... you will have to build and manage an economy, use counters correctly, and be fast to win. There will be a horde mentality to the combats, and the side with the most units and better production will usually win.
This is not WCIII. Or Medieval: Total War. It is Age... Civilization meets the Original WarCraft. It is a terrific refinement of the system, but it it still Age. If you don't want to play with armies and myth units, you're probably playing the wrong game. If you want an RTS-lite experience, you're probably playing the wrong game. If you want to play a game without an economy, you are DEFINITELY playing the wrong game. And this leads me to my last point.
NEW STUFF:
There is plenty of new stuff in this game, nuances that are not obvious in the demo. The Norse and Egyptians put all kinds of strain on the build-order fueled mind, and your own god selection compared to that of your opponents adds so much to the game.
Figure out ways to counter those damned Greek Heroes, when Perseus is accompanied by three Medusa and an army of hoplites. Concern yourself with the army of Hersir and Huskarls outside your gate as you cower with a battallion of Toxotes and manticores. Decide how to break out of your Egyptian stronghold... elephants or chariots, myth units or counter rush?
I pre-bought the Collector's Edition, and nothing I have seen has made me regret one penny of the cost.
Final Thought:
It's a sequel, people. I won't expect to go to Spider-Man II and see a period drama, and I don't go into Age of Mythology expecting Medieval: Total War.
AoM is the real deal, a wonderful game with a rfined system and tons of variety. A one civ demo isn't going to convey this. Trust the Alpha and Beta players... this game offers a lot.
From the briny depths of the Great Lakes comes... Clan Chowder!
Anxiously awaiting the Age of Mythology board game...