Official expansion talent previews

[Quark]

And I'm saying you have to wait until beta to call the talent a failure

No. Not with the history of the rogue class. Our review would have looked exactly like the first glimpse if we had done nothing about it. Blizzard is showing us time and time again that they have no concept of Rogue balance until they hear back from the players. I don't need to be in game to know how much Suprise Attacks sucks.

~40% damage is Backstabs

60% crit at 2.24x damage (4/5 Lethality) = 1.344
35% hit at 1x damage = 0.35
5% dodge

1.344 + 0.35 = 1.694

60% crit at 2.24x = 1.344
40% hit at 1x damage = 0.40

1.344 + 0.40 = 1.744

(1.744 - 1.694) / 1.744 = .2867

2.867% Increase in backstab DPS

1.147% Increase in total DPS

Those scratch notes took me 5 minutes, and exclude the energy cost modifier. Know what talents provide a bigger DPS increase per point? Opportunity, Improved Slice and Dice (first two points), Improved Backstab, Relentless Strikes, Dual Wield Specialization, Blade Flurry (even versus single targets), Weapon Expertise, Adrenaline Rush all off the top of my head I know provide a bigger increase.

Besides, the new combat talents look mostly PvP oriented to me, and it seems like not being dodged (especially on gouge) would be a very good thing there. In addition, in smaller raids stunlocking will be more viable, and this talent would help with that.

PvP: players already cannot dodge from behind (though mobs can), so there goes half of that advantage. Let's look a little deeper, then.
Shaman: not really a factor.
Mages: not really a factor.
Warlocks: not really a factor.
Priests: not really a factor.
Paladins: small help.
Druids: caster not a factor, cat/bear help.
Warriors: help.
Hunters: help.
Rogues: big help.

... So wait, I'm supposed to be happy about a change where if a Rogue specs it the person that suffers the most is me? Besides the fact that someone who goes 31 points into Combat is not speccing for PvP in the first place.

Additionally, stunlocking in raids is a myth. Stunning helps sometimes, but diminishing returns make a stunlock impossible. And then we're back to the whole useful/required argument. If Blizzard makes getting rid of a 5% non-landing rate on stuns good, then they have a good chance of making it necessary, and forcing spec.

Also, as well as continuing to assume that crit will be as easy to obtain, you assume that capping +hit is also obtainable. That can mess up your numbers a bit too.

Crit/hit bonus from items is changing in the expansion. I know that much from item screenshots where crit/hit is given a "rating". My guess is for two reasons:
So that, say, 1% crit on an item (which take 29.5 agility at 60 for a rogue to get) would become 1% at 60, but only 0.85% at 70 (which should require 34.4 agility if the pattern continues).
So that an item can have partial crit/hit.

But this is all irrelevant. Others have shown that SS at 30% crit still suffers the same flaw from this talent, just not as much. I have 40% backstab crits from talents, and even if my crit from agi/items is halved I'm left at over 50%. Meanwhile, I have 5% hit from talents. Again, if my %hit is halved I'm still left at +11% hit which is still much more than I need for +3 level mobs.

Drastic changes in the combat system wouldn't remove the flaw in the talent.