Lots of changes in the rules, as could be expected. One trend I don't like is the simplifying of unit choices. The Ork Boys lost their burnas last codex and they didn't get them back this time either. Why not? It's not like they have a strict tactical doctrine. The orks need more choices in options for their staple unit, not less.
The same goes for the Big Mek, and the welcome addition, Mekboy. They have fewer weapon and gear choices than last codex. I have a kustomized big Mek with a burna I built years back. Which is now not an option in the new book. Good thing Orks don't give a toss about the Man's rules.
On the plus side, Tankbustas, Burnaboys, Lootas, and Flash Gitz can all now take a Trukk as a transport. Bikerz, Killa Kans, and Warbuggies all got their squad sized increased. The killsaw is a great weapon for Mega-Nobs and Big-Meks for chopping up tanks.
The new Ork Horde FOC is kinda cool. They have one more HQ slot and three more troop slots, and a chance to get Hammer of Wrath. The Warlord traits are mostly good and you can re-roll for them if you are using a Ork Horde detachment FOC.
The Mob Rule has been changed to a table which has some nice Orkiness to it, Most Orks get 'Ere We Go which allows you to re-roll one die when charging. The Warboss still can call the Waaagh once a game, allowing the Orks to run and charge.
Orks are one of those armies the Unbound army list was made for. It was very hard or impossible to fully field a true Kult of Speed or Dread Mob before. No longer. We have only had one game with the new book so far, I took a Kult of Speed that had 1 HQ, 1 Elite, 4 troop, 3 heavy, and 5 fast attack choices. Nothing totally cheesy or out of character but a lot of fun. I'm putting the finishing touches on a Gorkanaut and then it is Dread Mob time!
Stomp some 'ummies!
And 'ery one else