Data point:
I flew in the exit row DCA-DFW 6/14. I ordered a woodford on the rocks and the flight attendant held his hand out for my credit card. I started to go through the motions of handing him my card and remembered the drink benefit. I asked "hasn't the main cabin extra drink benefit started?" He looked a bit perplexed and said something to the other FA on the cart.
I couldn't hear them very well, but the other FA pointed to the main cabin extra placard above the seat and also pointed at the tablet. I think I heard him say something about the tablet also indicating the drink should be free. The FA serving my row apologized and handed me the drink.
Not a big deal but I agree with everyone who has posted that this should be a really simple rollout but somehow has been flubbed. There should be few if any reports that people in rows designated as MCE are being asked to pay for something that they shouldn't have to pay for - this isn't rocket science!