Being up-to-date with the manga(issue 45) I'd like to give my take on things.
Eren father is a HUGE key player(enemy of the citadel), wouldn't be surprised if he is the big hairy one(still, that hairy one was surprised to find the 3d gear, so that's a no-but maybe he never saw it before in action-)
The titans are engineered, they lack reproductive organs, this is done by people who somehow knew how to control the titans. They actually listen to some of the intelligent ones(read: like the hairy one). Eren father is/will be found out to be quite knowledgeable on this matter, if not the progenitor(or along the lineage of the original one).
Eren, Annie, Ymir, Berthold and Reiner(and more) are second generation Titans... some aware of what they are, and trained by the predecessors: the first generation. Other will find out about their powers. Eren's power will be the ability to shape his body.
I wouldn't be surprised if Annie and Eren are half brother and sister(HUGE SPOILER, I think the writer is inspired with Greek mythology, and if you are acquainted: those stories go pretty Shakespearean with the family ties. So there will be a triangle Eren-Mikasa-Annie thing going on... Annie will be TnJ'd be Armin later on.
The Titans in the walls are for the safekeeping of the human race, not to protect the flock, but to save some when the time comes. See it like Noah's arc-which bring me to the last thing: the walls are one huge prison for the humans... Berthold, Reiner, and probably Annie(I don't think she's in the same league-might be- with the latter) will want to bring down the Church, and the Aristocrats-who are keeping the budgets in check so that the army doesn't advance too fast too soon.
Eren father is a HUGE key player(enemy of the citadel), wouldn't be surprised if he is the big hairy one(still, that hairy one was surprised to find the 3d gear, so that's a no-but maybe he never saw it before in action-)
The titans are engineered, they lack reproductive organs, this is done by people who somehow knew how to control the titans. They actually listen to some of the intelligent ones(read: like the hairy one). Eren father is/will be found out to be quite knowledgeable on this matter, if not the progenitor(or along the lineage of the original one).
Eren, Annie, Ymir, Berthold and Reiner(and more) are second generation Titans... some aware of what they are, and trained by the predecessors: the first generation. Other will find out about their powers. Eren's power will be the ability to shape his body.
I wouldn't be surprised if Annie and Eren are half brother and sister(HUGE SPOILER, I think the writer is inspired with Greek mythology, and if you are acquainted: those stories go pretty Shakespearean with the family ties. So there will be a triangle Eren-Mikasa-Annie thing going on... Annie will be TnJ'd be Armin later on.
The Titans in the walls are for the safekeeping of the human race, not to protect the flock, but to save some when the time comes. See it like Noah's arc-which bring me to the last thing: the walls are one huge prison for the humans... Berthold, Reiner, and probably Annie(I don't think she's in the same league-might be- with the latter) will want to bring down the Church, and the Aristocrats-who are keeping the budgets in check so that the army doesn't advance too fast too soon.