From what I understand, it's not that feats will really be less powerful, it is more than some things that were feats will now become class powers.
Anything that give you an active action/choice (power attack, improve trip, improve disarm, whirlwind attack, spring attack) will become one (or serveral similar) power(s).
Feats will be used to give passive/permanent bonuses :
- gain a new trained skill/skill focus
- some bonus to some skills (not only +X, but bonuses like rerolls, decreased time to use the skill, and so on ...)
- situationnal bonuses (alertness where you gain uncanny dodge, adept of the golden wyvern that allow some spell shaping, ...)
Those don't make you really stronger, but with them you can still fight at full efficiency in situations where others would not (do not give combat advangage when surprised, can launch an area spell even when allies are near, ...)
That's how it is possible to have a fighter taking only feats improving his social skills, and another taking only combat skills, without having the former be useless when compared to the second.
They both have the same base fighting power, but the fighter with all combat feats will be able to fight at peak efficiency more often, while the other will be better at handling social encounters.