First, you need to know the context of the remarks. Obama was visiting Mexico. Mexico complains about U.S. guns, not because it is a sizable crime problem; but because it is a lever to ask for more money out of the U.S. government.
Second, I have no doubts Obama will sign an AWB if it crosses his desk. The question is whether he would push for one; because without serious arm twisting from the Democratic leadership (to include the President), an AWB will never cross his desk. Even with serious arm-twisting, it isn't clear that one would cross his desk, so that is a big political risk to take.
Third, Obama did remark that he would like to adopt a 1997 weapons treaty that President Clinton proposed but that the Senate refused to ratify. I think we need to find that treaty and see what is in it - if Obama wants to pass gun laws, this is a very stealth way to do it - and even better, it only requires a vote in the Senate so it would be easier to pass. We definitely need to find out what is in that treaty and get vocal on that.
As far as a renewal of the federal AWB, I just don't see it happening this term. They don't have the votes right now and won't have until Feberuary 2011 at the earliest (unless they want to make it a major effort and they have too many other projects ahead of it). If they wait that long, it is campaign time already and Ohio, Florida and PA are still the critical states to win.