Well, GW can lick my (expunged by the holy orders of the Emperor's Inquisition), so you can ask me.
It might just be the fact that both local World Eaters players here are...erm... a bit shallow, but they're quite pleased with the change in Khorne Berserkers. WS5 means they're basically doing the same amount of damage in close combat through raw hits as they would with WS4 and a chainaxe, and for no change directly in points. Furious Charge is built in for the same cost that you'd pay for it in the current Codex though, so you're basically spending another three points per model for a superior fighting unit. No Blood Frenzy means you've got a bit too much control over Berserker units, imo... but the whole point of the Codex was to dumb it down for people like the local World Eaters players who are too dim to flip between an armoury page and the unit entry...
Emperor's Children are a bunch of punks, and always have been. The reason that the Blastmaster is 40 points is because it's able to put out a S8 AP3 small blast that causes pinning checks. Lash of Submission makes the enemy come to you, out of cover, and into charge range for your I5 Noise Marines, whose Aspiring Champions can use their doom sirens on to reduce to gibbering goo. Every time Lucius makes an armor save or an invulnerable save, the model that dealt the wound takes a S4 hit with no armor save allowed. The only thing that keeps that from being downright retarded, as opposed to just incredibly broken, is that the Lash of Torment reduces all enemy attacks against him by 1, to a minimum of 1. And Lucius has his power sword, which is sort of a moot point in the end... you almost WANT him to get pummelled...
True Grit is completely moot with the way the rules are set. Plague Marines may be I3 now, but they've still got a bolter, bolt pistol, and close combat weapon. It's still the same effect as True Grit, but you get a charge bonus and it's one fewer rule people who can't be bothered with subtle variations have to know. Have fun killing Plague Marines, though... of the cults, they're going to be the ones that are dominating everything since they're tactically flexible and obnoxiously hard to kill-- T4(5) with Feel No Pain means a Space Marine has to wound it on a 5+ with either bolter or chainsword, and then the Plague Marine has to subsequently fail its armour save and its Feel No Pain roll. T5 and Feel No Pain is better protection than Terminator Armour, and it's all rolled into a 23 point package. Oh, and they have krak grenades, too-- so even if you don't give the Aspiring Champion a power fist, that dreadnought that kills them on a 2+ to wound may be taking a couple glancing hits in return, so it's not like there's really even a safe way to go about neutralizing them. Their ONLY drawback is that they're I3, and it just downright doesn't matter since they're so hard to kill. Typhus, like Lucius and Abaddon, is kind of a waste of points unless you're sure he can kill about twice his points value. The odds of rolling a 1 and wounding the character with the daemon weapon are quite high-- in fact, in a single game, the probability is almost 1. And a 1 means not only do you not get to attack, but you take a wound with no armor save or invulnerable save allowed. And remember, a wounded independent character is worth half his victory points. Yes, he may have a force weapon manreaper, but you know... at the expense of handing your opponent 113 victory points with a probability of nearly 1, it's kind of not worth it... it's better to just take a terminator lord with a power weapon.
Here's why Thousand Sons are 23 points apiece. Against a solid 80% of the weapons in the game, your 4+ invulnerable save counts for a whole lot of nothing. AP3 is just as good as AP5 against quite a few things as well-- only against Space Marines are the Inferno Bolts valuable, and while there are still a disproportionate number of Space Marines running around tabletops, there are a drastically increasing number of Imperial Guard and Tau players.
Also, Thousand Sons are tactically inflexible, which makes them far less useful in a tournament setting particularly than their entry in the Codex would otherwise suggest. The sorcerer's inability to take any equipment is, to put it mildly, removing one of the squad's testicles, and giving them such specialized abilities (basically, Space Marine hunters) at the expense of tactical flexibility means that if there's nothing for them to specifically go after, they're not really doing anything useful for you, and they're a lot of points to be effectively a dead weight.