Yea its 2 game modes. I think the first is skirmish. 1v1's and 2v2's. However, a premium member can only invite people into games, but a free player can be invited.
The other game mode i believe is 4v4, 5v5 ect..
They have taken away all offline game modes, but instead gave missions online. For example, build 5 farms and defend an enemy attack within a time frame, or make 5 guard towers and mine 400 gold within a time scale.. things like that, get you XP. Its hard to figure it all out really, im just going to buy it and mess with it because its supposed to be the most in depth game of the AOE series ever relased.