I can't see into the man's heart, but my take on it is that he leans pro-life, but showed pro-choice for political expediency.
That being said, a president's ability to affect the abortion question lies in judicial appointments. Our options are a man who promises to continue to appoint pro-abortion justices, or a man who says he won't but can't be trusted. If we are analyzing the decision on the basis of sin alone, the choice is clear as far as I am concerned.
I have told you this before, but I will remind you that I weigh the abortion issue over all other issues combined in an election. I would vote for a down the line liberal who was otherwise pro-life over a hard-core conservative who was pro-choice.