Jobs won't have levels and as such won't need to be leveled up. Jobs are an advanced form of the class that unlocks them. So for example purposes, a level 50 Gladiator would be a level 50 Paladin. (Example only!)
Also we can confirm that we'll be changing the term "ranks" (as in rank 50 Pugilist) to "levels" (as in level 50 Pugilist) along with the removal of the physical level. We'll also be changing skill points to experience points.
In summation:
Rank > Level
Skill points > Experience points