Chris M.wrote a review of Black Diamond Cayenne Glove - Women's on February 17, 2013
Familiarity: I've used it several times
I did a lot of research for heated gloves before choosing this one, at a somewhat of a risk, at backcountry.com. First, on the glove. My wife has sensitive hands and we have tried many approaches for skiing. We have tried various heavy duty mittens such as those for OR, which are fantastically warm, but so bulky that they are impractical. Worse yet is that they do not deal with her thumb coldness.
Next I did a lot of research on heated gloves, but was unimpressed by the size of the batteries on NiMH based systems. Of the Li ion powered options, none seemed to have small women's sizes (my wife is a women's ~6.5).
Finally I found these. I wasn't familiar with Black Diamond, but was impressed by the reviews of their other products so took a chance. I couldn't be more pleased. The gloves are really high quality, and quite warm as conventional gloves with heating element off. My wife found them fine for temps in the 40's. For temps in the 20's, she has found the low setting (37 deg C) okay, and for lower than that, the medium seems good (42 deg C), and finally her thumbs are warm!
I would highly recommend this to anyone interested in getting something warm to ski with.