Imagine the value Google will be able to provide advertisers correlating regional temperature preferences/settings and purchasing habits / levels. Homes that set their thermostat to 72 degrees during the winter months in the Midwest = Lexus ads or tropical vacation ads, 64 to 72 degrees = Toyota ads, less than 64 = [some brand or store] ads for bed comforters.

ADD: And then in summer months... setting at 72 or less = Mercedes ads, 72 - 77 = mid income ads, > 77 = Fans and air conditioner ads.