I honestly think it comes down to this: Coach Saban is not satisfied at Alabama. But Coach Saban would not be satisfied anywhere... that's the price you pay when you base your happiness around always striving to achieve an unachievable standard. I do think the process of building is more satisfying to him than sustaining, though. Hence, he considers moving on.
However, I take him at his word when he says he's too old to start over. So, where does that leave him? Not satisfied with where he is, but not sure he can start over, either. So, he sends mixed messages, and is indecisive. Totally normal, if you ask me. And it seems clear that he is not ready to retire, either.
My guess is that he's going to think about this for a while. He's going to leave his options open. And it's going to be unpleasant for us, but this is the price we pay for all the good we've gotten because of him over the past years. If he does decide to leave, even for Texas, count me among the ones who will not be bitter. After all, his leaving would come from the same personality traits that have made him (and our team) so great. Can't fault him for being who he is.