It's fun to try to master all the civs, learning and using each civ's strong points. You can even create your own scenarios, which can then be traded and played by other players. The replayability of this game is one of it's strong suits. For a 2D game, the graphics are exceptional. Definitely worth a look.
Sounds are excellent.
3D sound effects are pretty good. Go get this game. All of the new units look great and have improved compared to the old ones. I like all the new options such as the buttons for seeing your population and the one for when someone is fighting. Playing the game is very addictive and if it's multiplayer, that's even more addictive.