I had already posted this in the there is no dancer (yet) thread, but I have a bad feeling it'll get drowned out, so I'll post this theory here as well.
Some people say that in the trailer they used some of the monk forms like fists of fire and fists of wind. Now with that in mind remember what was mentioned at the fest about the battle system getting updated, and useless skills getting repurposed. Featherfoot isn't the only pointless skill in the monks endgame arsenal, two of our forms can't ever be used during an endgame battle by any means: the fists of wind and the fists of earth. So, what if the devs update the other two forms to change the monks fighting style? And not just change the fighting style, but change the abilities as well to suit the different form of martial arts?
We'll use the trailer as a good example for that. If the forms did get repurposed then the monk could change their style to suit that form as said before. The fists of fire being a more offence, heavy attacker focused form.
The fists of wind being perhaps, a more lightweight and flowing form like how the woman in the trailer was. Maybe something that promotes fast attacks and evasion.
The fists of earth would be a tough one to pin down, obviously since it was a form used for defense at earlier levels, maybe it would promote a higher defense and could possibly focus on something like counterattacking, or using the damage they receive to buff themselves.
Just some speculation there on my part. If there are any martial artists on this forum that would like to help elaborate on this, please do.