they just realy spoke about possible game mechanics and story, on a basic level there theory was, this will be a more acrobatic game(similar to DMC2 apparently) with wall running and air dashes they also spoke a bit about his weapon he uses in the trailer that seems to transform into a spear,axe,sword and grappling device that will hopefully interact with the scenery(throwing cars etc).
They speculated that the story may take place at two purgatory(heaven/hell) times that run simultaneously with each other(Dante fighting and Dante being tortured)although there story speculations didnt realy make much sense to me.