Pretty cool! As others mentioned, color blindness is an important consideration (affects 9% of men), so having an alternate way of expressing the heat map would

Pretty cool! As others mentioned, color blindness is an important consideration (affects 9% of men), so having an alternate way of expressing the heat map would be useful. But for folks without that issue (I dodged it, even though it runs in my family), I think the current implementation is intuitive and works well. Up next, Dvorakle?