1914 already has absolutely no meaning for the average Witness. Unlike most of us who grew up on the "generation" doctrine, today's witnesses have no chronological means to set a boundary for The End. As time passes, 1914 will become less and less relevant to Witnesses.
That being said, the WTS will continue to use 1914 as the date for (1) the end of the Seven Gentile Times (whatever that means); and (2) the beginning of Jesus' invisible presence in kingdom power.
Sure, every year they look dumber and dumber, but that's not going to stop them. Remember that the Seventh Day Adventists still hang onto 1844 as a critical year--that's 165 years ago! If they can hang onto 1844, I think the WTS can hang onto 1914 for several more decades.