I heard theres also gonna be a PS3 version?
Anyway some stuff i learned trying to find out more about blade n soul a long time ago was each class has an "mp" bar, but each one is called something else and i'd guess each one allows for use of skills. Hard to explain >_>
Combo system from what i've seen is really ffffing amazing as you have an 8(?) button skill hotkey list and each time you use one of the skills the whole hotkey list will change to what you've set it to or something along those lines. Example: lets say you have a skill called Kick, and then other skills like Punch and Uppercut. You use Kick and then your skill hotkey list will change to a choice of Punch or Uppercut and then it will change again to Kick and Uppercut(if you used Punch)/theres a shat ton of skill i think so combos will be hopefully all your own and enables lots of variation. I'm guessing that since the melee classes have their "mp" bar as a bar with some number of circles/balls and each skill uses a number of balls so that there is no same skill spam combo and limits how long your combos are.