I also read somewhere that they are going to make adding multiple materia to items easier than it was. I suspect they will do this by just upping the probabilities of success. Can't remember where i read it and can't find source - so maybe I dreamed it.
You either saw it or read it from the 4th live letter from the producer. Yoshi didn't come out and say they were, but did say they were considering it. With all the complaints about how horrid it was to double meld weapons for the relic quest, it really shouldn't come as a surprise if they do. I was lucky with mine, but I farmed a bunch of gil expecting to fail and have to pay 30+ million gil for mine. I melded mine first try for 3.1 mil. That's even after I made 1 of the two materia I needed for it. Very risky, but felt oh so good when it happened!