Don't expect these to hit retail till late 2018 or 2019 (safer bet), Since Samsung have been fucking around and are happy to keep pumping out LCD sets for consumers atm. Though, thanks to pressure from LG & OLED maybe they'll get off their ass.
Also, due to the way this, OLED (Direct View not the LCD shit), Plasma, and even CRT works "image persistence" can be a slight issue, but you should not have to worry about it at all on good sets. Also, keep in mind it is quickly to go away depending on the manufacture of your panel and what they have put in place to insure it is never permeant.
My 60" Pioneer Kuro is freaking beast when it comes to avoiding "image persistence", thanks to all the tech and methods Pioneer used to ensure it was not a issue or would quickly go away as soon as you switched content.
Also, this article really does not point out the biggest advantage of proper QLED which will be 100% coverage of the Rec.2020 standard which pretty much only QLED & Lazer projectors will be able to obtain unless other display tech improves a fuckton in next year or two.
Future developments & goals when it comes to tv tech under current standards are: 10,000 nits, 100% Rec.2020 coverage, High refresh rate (expect this to start rolling out next year), higher bitrate panels, & more pixels of course.
P.S Expect the sets to cost a premium as always when new tech is introduced. Samsung will want to recoup as much many as possible off early adopters in high end display market.