Who's to say that the new jobs won't have special skills they learn through quests that can't be cross classed but still have other "cross class/job" abilities in order to meet the current structure? Just because they removed the word class from the equation doesn't mean we won't still have some abilities from other jobs to use. Personally, with the lvl cap going up to 60 I'm hoping they open it up more and allow for some more hybrid customizations.