Classes - Jobs - doesn't much matter what you call them, they are more or less the same thing. That being said I personally find the classes as implemented much more fun than the jobs: The guilds, the early quests, huntlogs. Those are currently only available for classes in the game, not for the jobs.
Should they be stupid enough to actually remove the classes without including all of the current class content in the jobs, then I would seriously have to consider leaving the game - that would be too big a change for no good reason.