Let's break it down.
Courage of the Lion now only applies to Leadership tests for morale. Nothing more to say.
Stasis Anomalies and Vast Stasis Anomalies don't stack together. I guess this was a big issue? Not having used a Dark Talon I can't say I ever thought about it.
Power Field Generators - If the bearer is embarked upon a Transport vehicle, the
powerfield’s effects only apply to models embarked upon that
vehicle” - This always seemed likely to me, however I would have thought they would have let the vehicle itself have the PFG's save. Seems like GW have broken their own rules on area effects when boarded on vehicles, but as I haven't really dived into the world of PFG's it's not something I'll miss.
Asmodai finally gets a bolt pistol. Really not ever going to make me take him, but at least he can use more than harsh language at range now.
Deathwing Command Squad options are now clarified. Don't think anyone thought these would work any other way, but now you know an apothecary can't get a 3++
Ravenwing Command Squads - Well, this is the biggie here. An extra two Black Knights at 40 pts each!! this means that you can have a few bikes drop before your Standard of Devastation gets killed. Really don't see how anyone would consider taking other command squads now. 295 pts gets you 4 Knights, an Apothecary and the SoD. A little expensive maybe, but you have a banner that can be put where you need it, multiple saves and FNP, and can be used to redeploy and Plasma Talon anything that threatens your gunline. To me that's an autopick in most lists in place of any Black Knights if you have any characters on a bike or Sammael.
Deathwing Sargeants cannot now replace their initial loadout. Erm, why? Not sure what the purpose of this is, as they were hardly overpowered by taking a TH/SS, and I'm sure most players have one or two Sarges with that or LC's. Odd, odd, odd, and probably soon to be altered
Deathwing Assault units do now count towards your 50% reserves. Guess all Deathwing armies were battering someone at GW HQ! But in all seriousness, I think anyone looking for another ruling was kinda pushing it. Shame, but them's the breaks.
Finally, a clarification on what counts as a bolter for the SoD effect. I would say this was fairly simple, but I've seen at least one forum post where they tried to claim that any gun listed under the 'Bolter' section in the Rulebook counted. This is probably going to convince me to bust out the old Land Raider Crusader I have stashed somewhere, so that's good :P
So, some good, some not so hot. It's not exactly the end of days that some on the internet are claiming, probably due to the PFG ruling, but seeing how many you can fit in an army it was always going to happen. I can safely say that the Ravenwing Command boost makes me want to buy another Black Knight box, so I guess that's a win from GW's perspective. Yay for painting more Black Knights!