I just don't see how a grown man can be contracted to marry by his mother in a patriarchal society like the one presented. Another thing that makes more sense in the books, maybe, since Robb is only supposed to be 17 or 18 at most, and not a grown man like the actor? I can see Catelyn making a contract for Arya (who will certainly object if she's ever reunited with the family) or for Sansa, but not for an adult son. Not a binding contract in which the son had no part of negotiating. Catelyn agreed to the marriage so Frey would let their army cross the bridge to go save Ned, but Ned was murdered right afterwards. So, the contract's still valid? .
From what I hear, I fervently hope that one particular plot point from the books isn't followed.
I give the writers all sorts of props for killing off a lead character in Ned and following the books. It drives story and it was ballsy as hell but dammit....Robb is Ned now. It sucked losing my favorite character; I don't want Ned 2.0 to die just because his mommy made a marriage contract and he married someone else. What a lame reason for him to die.
Robb, Tyrion, Arya, Brandon and Cercei are keepers. Everyone else is negotiable, including Jon....though I know he won't get the axe.