I've been waiting for A2 cow's milk for years. It's basically the original cow's milk before modern farming practices mutated cow's milk proteins from A2 into A1 protein (casein).
Could not believe my eyes when I saw A2 milk on the shelf at Whole Foods today for the first time. For the past 8 years I have drunk goat milk, which has A2 protein and tastes good but costs twice what cow's milk costs.
I had first tried A2 milk last winter break in Cold Storage supermarket in Singapore--in long-life box form--but did not expect to see it in the US for another 5 or 10 years.
A1 protein causes allergies and phlegm and is linked to indigestion and autism. A2 has none of the side effects (although if you are lactose intolerant it does have lactose).