I like the idea of jobs not having their own levels, because I think it gives each job+class set a viable option for small groups, soloing, and PvP as well as serious party play where everyone has a role. This is something that has long eluded most MMO developers, trying to balance content that is best done with generalists with content that is best done with specialists. By always having a job and a class to choose from, this problem may very well be solved for FFXIV, without making everyone so similar it doesn't matter what class you are or specializing them all so much they can't kill a rat solo.

However, I do think that they need to make good on their promise to give jobs their own growth through quests. If we just end up with 3-5 per job for one new ability each then it will feel like there isn't enough content or lore for the jobs to exist in the game, and it may not be enough to give them the advantages they need in order for jobs to clearly be the better choice for parties. We need to have many quests for both abilities and equipment, and then it will be fine.

They definitely have their work cut out for them, considering every new addition to the game will require both a class and a job to be balanced separately (but with some of the same abilities and strengths), and jobs will all come with several quests.