This is a few years away but would be awesome for me.http://www.news.com.au/travel/travel-updates/qantas-considering-direct-flight-from-sydney-to-new-york/news-story/feb6d225cd1edd2648a5a5667551a0b4
Direct JFK-SYD flights possible, but not until 2022. It would save me 4-6 hours and a stop over in LAX when I go back to Aus to visit my family.
Delta, could possibly conduct non-stop ATL-SYD flights when they take delivery of their A-350's. The problem being, is that there is not a single, (to my knowledge), CAT III approach on the whole Australian Continent (SYD included) thereby adversely affecting the reserve fuel requirements for arriving aircraft.
B-787 and B-777X aircraft may be able to overcome this issue out of JFK.