Went to one of my favorite breweries on Saturday and they had a cherry sour made with lactose and vanilla, so basically a milkshake sour rather than the increasingly prevalent milkshake IPA. Keith, have you seen this catching on? It was amazing so I'd be pretty excited about that trend since I've found milkshake IPAs less dependable than I had hoped after discovering them via Tired Hands. I've only had one truly great milkshake IPA from these parts, a coconut one that went with the tropical hop palate to really hit the spot.
Yeah, the J.R.E.A.M. series from Burley Oak is mostly responsible for the juicy lactose sour thing from what I know. Some of them I've really liked, others have come off crazy tart and bitter (depends on the fruit additions). They don't ship to well from what I've heard though, the 'wild' yeast don't get happy at higher temps. They've also done soft serve versions!