There are a number of small changes to the fighter class (and the game in general that I think will greatly benefit them in the long run).
Skills and Saves: Fighters now begin with 4 skill points and a good Will save.
Feats: Most Combat feats have now been combined to provide auto-scaling of abilities. This is one of the most dramatic changes to the game and will alter play on both sides of the table. It is also the is one of the areas that needs more extensive playtesting.
Bonus Feats: Fighter “bonus feats” now include Combat, Critical, Style, and Teamwork feats.
Feat Prerequisites/Rules: Fighters no longer need to meet ability requirements for Combat, Critical, Style, and Teamwork feats. Any feat that is applied to a specific weapon instead applies to a weapon group. So a cleric could take Weapon Focus (mace), but fighters take Weapon Focus (hammers).
Stamina Pool: All fighters can a pool of stamina points that can be used to provide additional benefits to most Combat and Critical feats. Short rests between battles help fighters recover stamina points.
Armor Training/Weapon Training: Neither of these have been formally changed, however the changes to feats (above) and the changes to ACP (previous post) make both of these abilities now far more valuable.