Dark Knight

[Gamemako]

i just want to see proof that there will be Dark knight.

There is none. No new jobs have been confirmed. People just like to talk about what they want to see. Yoshi has used Dark Knight as an example when talking about a possible second job for Gladiator, but that does not mean Dark Knight will be the second job for Gladiator or even that we'll see Dark Knight at all.

there aren't any two handed swords in this game, or duel weilding...Who does that?

It's dual, not duel. Each class has its own weapon set, so any new class would need a new weapon set. Additionally, the pugilist weapons are dual-wielded, and any future dual-wield weapons will likely be done the same way.

there just has to be upcoming jobs/classes that have these skills, otherwise everyone will get bored and just put the game down and play something else.

If people are quitting because of a lack of dual-wielding, I don't mind.