What I expect is that any "add-on" support will be limited to only information that is available on-screen already. To do otherwise would give PC players an extremely unfair advantage over console users. I'd expect that no addon's would be allowed that would let you fire skills faster or more accurately than the existing macros, nor would any addon's allow "choreography" in absolute positions. Maybe relative positions (eg "strafe 10 steps left, walk 4 steps forward, wave, smile") in the same way cutscenes work would be something cool to do and let RP'ers do more than just talk.