Yes, the Verizon Note 4 Marshmallow update is now live, and it comes as an OTA whose build no. is N910VVRU2CPD1 (based on stock Android build MMB29M).
If you own a Note 4 at Verizon, now’s a good time to hit up Settings, and look for a system update. Make sure you are connected to WiFi as this could be a big update.
As for the changelog, Marshmallow brings with it its special set of features that includes Doze mode (better battery life), app permissions control, Now on Tap, etc. besides the significant under the hood improvements resulting in more stable OS and smoother usage experience.
Verizon has put in some new features with the Marshmallow update as well: You are looking at ability to make WiFi calls, HiFi Audio enabled, and some changes to UI by Samsung here and there — but nut much. Amazon Music gets an Axe btw.