I think this release was slightly underwhelming. They fixed couple of things and it took two years. On the other hand it's understandable when you look at the mess which is Nethack's source code. It's not easy to maintain I would guess. Even so I was expecting more gameplay changes, new stuff etc. but it looks like they "freeze" this version branch and the next one will have more changes so people who want to continue play 3.6.x can do that. There are people who believe some specific version to be the only real Nethack.
The way player character's name is highlighted when your HP is not full is a nice feature, it's something you'll notice right away. Other thing I noticed is that $ keyboard command doesn't work when picking up items, but I did comment out "Finnish keyboard" section in defaults.nh, maybe I should try to comment it again to see if it works. In Finnish keyboard $ is typed as AltGr + 4 and some other keyboard commands are also different. Also, the .exe was acting strange way when I started it the first time, it hanged for like five minutes and then Windows 10 smartscreen catched it, but I ran it anyway. It may be just the smartscreen, it's warning about everything.
Even I'm whining I actually like Nethack. It's really the only roguelike game I'm playing even I'm not a good Nethack player. I know what happens in the game later, I've seen gameplay videos and tried in wizard mode, but I probably like the beginning before Quest more than anything else. It's the way things start to go, sometimes you get very lucky and sometimes you get hardships. The first time I tried this version I managed to blow up my pet with a gas spore, and then turned into a werewolf. I also learned something new: when you kick a pile of gold it scatters around. I had to try that to pick up only gold, because $ key doesn't work.
One of the reasons why roguelikes are nice games is that you don't have to win. At least it's what I think about the genre. Those people who want to win will push it through by learning strategies you need to win this game, but I think when you don't learn them it can be just as fun.