Naturally with ASICS coming out, scrypt based coins will be the only ones available to the common masses. I wouldn't say that ASICS would destroy the bitcoin, rather just make it so that only a small amount of people will be generating bitcoins because the difficulty will be so high. I think that there might be a dip in price because ASICS will be pumping out coins, but once the difficulty is raised to a certain point and the flow of bitcoins trickles down, the price will steadily rise again.