Well I expect that they will have to write a new combat mechanic all together for the MMO. D20 does not do well with more than about 8 people in a 'single engagement' or a single timeline fight due to it's reliance on initiative rolls etc.
To make it work they will most likely assign a 'weapon speed' to melee weapons and a 'cast time' to certain force powers. Special attacks will most likely be largely instant and separate from weapon speed and consume a 'mana/force/fatigue' bar. That would allow every character at as a separate entity without having to stop/slow/link time like d20 does.