I can't say for sure regarding the cooldown period, but if it does exist then it's important to remember that it has nothing to do with Bitcoin itself; it's just a Dwolla thing.
That's true, it's a issue with Dwolla not Bitcoin.
Although it is a problem that it's so damn difficult for me to get my money into any exchanges.
Of course in fairness my situation is unique. I'm an American with all my accounts in America but I don't actually live in America right now. So it means I don't have the options of physically walking into a store like I normally would. And trying to buy BTC in the country I'm living in simply isn't an easy process especially since I'm not a citizen.