AST and DRG are the jobs they mentioned with reworks so extensive that we won't see them until 7.0. But yes, you can essentially look at major reworks such as MCH in ShB and SMN in EW as new jobs. Then when we factor the amount of jobs we currently have and whatever gaps exist with the roles, a melee job that uses scouting gear is the safest prediction to make.
Speaking of the AST rework though, whatever they do I would still expect it to play like a healer. Any player who is already thinking or hoping they'll do something groundbreaking will be sorely disappointed. I figure I'll just throw that out there now.