These have me a little puzzled, possibly because as usual they are being driven by CC rather than FL. That said, and from a FL perspective:
PLD: Nerf to Guardian via recast. Why? Don't understand the fiddling with Sword/Shield Oath.
MNK, VPR & DRG: All buffed for potency. Likely makes sense.
SAM: Potency nerfs. Doesn't this make it even more of a one-trick pony?
BRD & MCH: Potency buffs. Don't really understand why. Maybe for MCH it makes sense. (Edit: the "why" here and for all other jobs is based on CC win-rates.)
BLM, SMN, PIC, SGE: No idea, don't play 'em, but I didn't have a sense they all needed to be buffed.
AST: Boom, meet the nerf bat. Surprised they acted so fast. The big one here is Heavy (and now Bind for the doublecast) only applying to the first target. I think that's going to make a big difference, along with the other nerfs.
Thoughts, comrades?