Just like grits and oatmeal are about the same, right?
Had an Italian uncle by marriage who would go on and on and on about how wonderful polenta was, and the complicated process you had to use to make the perfect serving of polenta.
I was about 14 and asked him what was polenta, and he told me, and I said, "sounds like grits". Thought he was going to have a stroke. For the next 50 years any time I wanted to get a rise out of him, all I had to say was something about polenta just being grits.
FWIW, both Emeril Lagasse and Mario Battali say they are the same.

