My 2016 15’’ MacBook Pro arrived yesterday (as one of the first). 63 of the 64 keys work fine. But the i-key most of the time types the letter twice. I suggest you test out your keyboard thoroughly. With auto-correct it can be easy to think it works. However, my password contains the letter i, and I quickly became super frustrated not being able to get my password right (come to think about it, maybe that's why they added Touch ID, so you don't need the keyboard for passwords). So take a document, turn off auto-correct, and check all the keys. I found that the failure happens more frequently with a slight delay before releasing the key.