The answer to your initial question will depend on how likely you feel Obama is to get what he wants on gun control. If you feel like it is going to happen, then buy it, because you will be kicking yourself if you miss the chance. But if you don't think it's really going to happen with another AWB like last time, then wait, and get a good deal once the market cools down.
Either way, if you are wrong, you will be pissed at yourself. And I don't think all the guns being bought will go back on the market immediately. The people who bought them for double will be hesitant to sell at normal prices. They will try to recoup what they lost, and there will be a whole bunch for sale at inflated prices. It will be interesting to see how it plays out. What we will all be looking for is the guy whose wife is pissed he bought the guns for no reason, and is making him sell to pay for baby stuff, etc.