I've heard this too but don't know a lot about wine. What I have noticed in my 26 years here is that there are more and more drinkable reds growing in the valley, you may not see it so much in the supermarkets but when you go on wine tours it seems like there's more selection of wines that need warmer weather so it does seem like a real possibility. The land is pretty densely farmed, though, so you'd either have to log some hills or displace other crops, not that that would be a problem if it promises to be lucrative.