No. This games needs 3 things.
2.Chocobos ( who can also jump)
In that order.
Please keep making threads and sining those petitions! We will get jump in game!
The things that jumping would fix could also be accomplished through terrain redesign. A redesign will almost certainly accompany or follow shortly after implementation of jumping, simply to keep the intended access routes the same; the devs won't let you take massive shortcuts they never intended you to. Jumping does allow for future designs to have a bit more flexibility to them, having the ability to leap a couple feet in the air means you can have your natural rocky staircase without worrying about clipping a poor lalafell to death. It can also allow for personal stylistic flair and additional battle strategy possibilities simply by nature of the game's already implemented hit-box sensitive targeting system. Jumping will never allow you to exploit it to gain an unfair advantage, as the viral nature of cool bugs in MMOs ensure that they will eventually be patched (rusty cap, salvage dupes etc...)
Given this, jumping is more of a neat feature rather than a necessary fix. It will take time to implement correctly given the work that has to go into both the landscape and the mechanics. It is also most definitely not a critical item that needs to be implemented right away, chocobos and airships are part of the critical items simply because transportation is a part of what needs modification in the game, but I'd rather see the battle system, class system, crafting, leves, quests, storyline, economic systems, parties, and linkshell setups worked on before they start adding things like jumping and swimming.
The game is at the very least trying to get overhauled, and there will be lots of changes in the near future I'm sure. Maybe jumping and swimming will find their way into the game, but I don't think it's right or logical to make them a priority over existing systems in need of a working.