I've tried low carb wine, and it was pretty good. I think it works better with a white wine, much like artificial sweeteners work better in citrus drinks than cola drinks.
Diabetics in particular shouldn't drink a lot, simply because most are on medications that are processed through the liver, and so is alcohol. It's easier on the liver if they don't drink much. However, with the low carb wines and beers on the market, at least a diabetic can enjoy one drink without worrying it will make his or her blood sugar skyrocket.