of course this is all guess work on my behalf. but i like to think its an educated guess with the info we have, we have been told that yoshi wants to balance out casters/mages there is not enough compared to DoW. he also said beastmaster/summoner was the DoM he had in mind for next, also in the live letters part 2, he did hint that we could get beastmaster/summoner before 2.0, i'm not going to look up to quote, but the hint was when he said "ppl might see these sooner than they think" so this makes me think they are hard at work on this and debuff mage is on the back burner not scraped. and finally the reason i am so sure we have a debuff mage to look forward to in 2.0, is because an arcanist would make a great debuff mage and the guild is already there.
of course all guess work on my part, but it seems like a plan to me