Lighting really screw up her face sometimes in W2, I think it might be the same in W3. She looked a little chubby in that romance promo shot, but not in the vids. I think in the game proper she'll look stunning.
Either way, I'm hyped about her alternate look. Sucks that we'll have to wait at least 3 weeks for it, though.
Yeah the wait is going to suck. About her looking chubby vs video. I think if people just look at the gif I posted it might seem odd as the gif is not perfect an even misses some subtle details. If you watch the very end of gametrailers review though she looks incredible. I think even after putting the W2 Triss side by side on my computer W3 Triss just looks great and it feels natural like all the characters I've seen so far.