I'm really on the fence about this. Most of the time in a group with 1-2 strong mobs and normals I have no problem but do take quite a bit of damage which is no problem thanks to the self heal.
On the other hand some solo boss mobs that theoretically should be doable seem way too hard. Just using Korriban as an example the bloodies skull quest beast absolutely owned me until I got Vette at which point it went down easy and this was at equal level and IIRC it was only classed as a strong mob not elite.
I've had zero problems with normal mobs so far though. Force Charge, Smash and a few vicious slashes (I think or whatever the default rage builder is at low levels) and any old combination finishes off packs of 3-5 normal mobs fine. Even with a strong or two in there as long as I have Vette they go down within seconds of the normal mobs.
Not tried tanking properly yet but I did a bit in the last beta weekend and we do seem to have some threat issues even when in the tank stance. I don't think AoE threat is the problem as much as the lack of a ranged threat builder. There are so many ranged mobs in the game that it seems like Smash and our other AoE abilities just don't have the range needed to keep threat on them.