While up to fairly recently that was true, there are new ASICs coming on the market that would allow for mining scrypt, but they are slow and expensive. (approx. the cost of GPUs, though they do take less power to run.)  As with all emerging technology, I expect the price to drop and the power to increase very quickly, but still as a proof of concept they do exist and are currently being prototyped/tested/reviewed all over the place.

I am curious what they will do to the litecoin/bitcoin exchange rate once they are in full-scale deployment like the current sha256 ones.