Malbec: If you're familiar with the history of the grape, it's native to France (or at least evolved into the international variety we know there) but really didn't gain a foothold until it found its way to South America. The reason? Mildew is common and in cooler climates, Malbec ends up watered down and so light you can almost see through it. In South America, it ends up closer to Merlot or Cabernet Sauvignon than anything else. As the climate warms, there are a number of regions throughout both California and Washington that could plant the grape and have it end up as an excellent, high end version of the grape.
Grenache and Other Rhone varieties: Grenache especially has a wide, wide range of outcomes based on where it is planted and how it it grown. Heck, how the canopy is managed has a huge effect on the final result of the wine in your glass. As the climate warms, some grapes like Merlot won't be able to hold out in their current vineyard locations. That could be true for Pinot Noir as well given market sentiment toward more acidic versions of the variety. Grenache is a logical alternative to both Merlot and Pinot Noir especially for vineyard owners needing to graft, it can both exist on the same rootstock and withstand more climate differences than perhaps any other grape: meaning vineyard owners won't be in this same position in the near future.
Pinotage: Yeah, yeah I know.....there's only 40 acres of the stuff in the state. But, it does grow well in warmer climates (that's literally the reason they developed it in South Africa in the first place). Plus wine consumers in America are already accustomed to hearing about Pinot Noir, perhaps ad naseaum. So why not tell them, Pinot Noir is one of the parents of this variety but that this grows better locally? Plus, Pinotage tends to keep acidity even in warmer climates, meaning it's a nice fit for consumer preferences.
All in all, climate change is going to be tough on the wine industry. Some vineyard locations won't be usable any longer and others will have the character of their wines changed, without any fault of the owners. Knowing a bit about the likely winners, is just as important as knowing about the likely losers, although that doesn't seem as fun to write about for some reason.
Owner and Proprietor of Uncorked Ventures an online wine club and gift basket company, one of the most enjoyable aspects to my job is meeting the people who craft the wines that we all enjoy.