Received my 2017 NEC a couple weeks ago. Just received my IAEI Analysis of Changes book.
The Analysis of changes is damn near as big as the NEC itself !
First and foremost, NFPA is in the book business. They need to keep those changes coming to sell a full array of new books every 3 years. I am not sure I really feel that much safer tho.
So far all I have seen on '17 is the PP Changes by Mike Holt. I have not looked at a lot yet.
Books will be ordered in a few months. NJ is not 'fast' in adopting the 'new' NEC, into the State UCC. Could be sometime in '18, then again, perhaps sooner.
We are still waiting for the 14 here and the 17 will be around 2020 if they stay on the same arc.