Given that this is the Theory section of the forum, would it be worth taking a look at the impact that this change has (if any) on rotations/gearing/etc? I'm thinking the following:
- high threat but low damage moves might as well drop from rotations. For warriors, that's probably another nail in the coffin of revenge, and concussion blow is probably not going to beat devastate on average.
- 'Threat' talents now have to make up their worth as 'dps' talents - which makes them a lot more like a luxury. You could imagine a pure utility warrior build that ignores all the damage talents: http://www.wowhead.com/talent#LMbZhb0oZcrGdRoRdMu - I'm not saying this is necessarily a smart idea, but if threat is a non-issue then there's certainly an argument to say "don't try to be a poor mans dps, get more utility". In a 10 man group, I'm going to guess that the tanks dps makes up a non-trivial percentage of total RDPS, but in a 25 man group...?
- when the fast vengeance stacking comes up, I guess that has some fairly significant implications for feral druids. I also assume it means that abilities like shockwave that scale very well with raw AP will be stronger much earlier in the fight.