http://www.otakutale.com/2015/sword-...ght-novels-do/
During the A-1 Pictures panel at Anime Expo 2015, President Tomonori Ochikoshi has revealed that the studio has no plans to slow down the production for future seasons of the Sword Art Online anime, as long as Reki Kawahara continues to write more light novels.
The Sword Art Online anime is not going away anytime soon. As long as the novels are continually being written the anime adaptation will not be too far behind. The question now is when?