Going by themes and referencing other Final Fantasy games (especially XI)

Marauder could get a Dark Knight job, with scythes and thm as sub
Lancer could get the samurai job. Not sure which sub it would be. Pgl doesn't really suit it all that much and if it was Gla, it would become a tank/dps hybrid
Archer would get Ranger
Thief will be implemented, either as class or job
Musketeer (gun class)... I'm hoping for a more support-ish class, but I'm not sure how it'll be implemented

I don't think we'll see gladiator getting a job with dual wielding. It'll have to be either a pure or hybrid tank. Pugilist, on the other hand.. There are martial arts swords and such, so they could be getting a dual wielding job. Actually, Ninja could very well be pgl second job, if the coming dagger class doesn't lend itself well towards that.