Does this mean no over-arching classes, or does that include the prospect of further customisation through sub-classes or something similar?
I can see why you wouldn't want any new classes, since the current system allows for massive flexibility. You could play a pure healer, a pure physical attack, a pure evade tank, an agile damage dealer, a two-handing barbarian, an arcane spellcaster, a summoner spec, a paladin type...the list goes on. Your 'class' just gives you particular perks and that's it.
I love that sort of flexible customisation, just so it's clear.