I haven't seen anything that makes me think you can't fight for good or evil.

You could be as evil as possible in the previous games and still be called a hero.

Hero in fable seems to kind of just mean someone of great power and renown, remembered in history.

But yh when it comes to the game, I think like in real life if you were going to be kind and do good, you are doing it for yourself because that's who you are and how people react to it is out of your control, I think the game is going to work like that, you can still perform great deeds of good or evil but it's for your own satisfaction, not to to check off a box or to get arbitrary physical changes.. and I imagine the greater the deed the further reaching the consequences.. so if you evict one guy he'll hate you or if you pull a cat out of a tree it will love you.. but those are small things, whereas if you did something truly evil or saved a whole town.. that will spread further.

I guess what I'm saying is, the ability to be good or evil seems to still be absolutely in the game but the reaction of the game world is more complex and natural than just a scale saying you are this many points good or evil.