On the 27th of December 2013, No stated that he would personally like to see a X-3 in an interview.
“If there’s enough demand, then we may possibly see new developments,” says Nojima on the subject of a possible third installment of the Final Fantasy X series. “I would personally like to see a sequel like X-3.”
see the full interview here:
http://www.siliconera.com/2013/12/26/final-fantasy-x-scenario-writer-possibility-final-fantasy-x-3/As of the 8 January 2014, he was interviewed further, even going so far as saying he has thoughts on what should be in the sequel:
"Nojima recently mentioned that he’d like to see a sequel to the series with a possible Final Fantasy X-3. Famitsu asks him what kind of story would he write if a sequel were to be put into motion.
“It’s a secret,” says Nojima with a laugh."
On the audio drama:
“I wrote it while thinking ‘this should be a game’,” says Nojima. “So it was a mix of thinking ‘ahh, all the spoilers’ and ‘but I would want to surprise them’ and things like that. For the record, there’s a plot from start to finish, and if there’s some way we can have it show up elsewhere… well, so I’ve said to Square Enix."
full interview here:
http://www.siliconera.com/2014/01/08/final-fantasy-x-writer-shares-thoughts-memories-series/NEWS as February 2014
Thanks to Ananda we've heard that SE is not looking to do a X-3 but looking to "expand X's universe" through the audio drama and novel:
On the 13th February 2014, Shinji Hashimoto, the series producer said "the audio episode’s inclusion wasn’t because we have any plans to develop a Final Fantasy X-3"
Read more here:
http://www.novacrystallis.com/2014/02/square-enix-still-has-no-plans-for-final-fantasy-xii-hd-says-fans-need-to-demand-it/This was further confirmed in this article:
http://kotaku.com/no-final-fantasy-x-3-on-the-way-in-an-interview-with-s-1521996804Will update when more info becomes available....