The article was too non-committal with the results. The OLED gives a better experience because of the infinite contrast, not because of the total black level. The infinite contrast also works with all the colors including one missed point. The OLED technology also includes a white pixel and this makes a HUGE improvement in the overall image quality compared to the extended passive technology of the QLED.
Also, the added brightness of the QLEDs is overkill when watching in a normal living room, especially at night and most viewers will need to turn the brightness down for a more appealing and non-cartoonish image. If your viewing location is full sun brightness, then QLED may be a better choice for maybe a patio or pool location where bright uncontrollable light is an issue. But indoors where you can control the light levels, the ultimate image is OLED even in a fully lamp lit room. With the price being so similar, the difference in $6000 to $6500 is minimal to get a real State of the Art display.
Is Samsung hiring Spicer to write QLED copy? At $1K more than OLED's for a given size, inability to go total black QLED's look worse and cost more. I have been a TV aficionado for some time, have grown to prefer Samsung - while I wait for a Lotto win to afford an OLED. Now here comes QLED series, a step down from the KS series it replaces and $1K more than LG's OLED's. For my money I would go out and buy 65" KS8500 or 8K's for $1200 before the last of the inventories are gone. Hey that's what I actually did. What a bargain. QLED is not.
This article doesn't begin to correctly explain the usual technology for quantum dot LCD displays, or if there's actually anything different about Samsung's version, now that they're calling it QLED rather than the previous names. Samsung called them Nanocrystal displays when they first came out, then Quantum Dot, and now QLED, but it's all essentially refinements of the same thing.
The regular LED-backlit LCD displays use a white LED backlight. Of course, there isn't any actual white LED, so these are often blue LEDs with a yellow phosphor. That delivers white, more or less, but it's not as wide spectrum as you'd get from most other light sources.
Quantum dots are intersting because they have artificial band gaps -- the constrained size of the particle accurately defines the band gap, and thus, the light that they'll emit when excited by some other source of energy. In the case of QD-LED displays of all kinds, they use a blue LED as a backlight (you need a higher energy source to excite the quantum dot), then precisely calibrated red and green quantum dots, which work together to deliver a wide spectrum, pure white backlight.
Certainly other things could be done with quantum dots and displays, but no one's building an all-LED display after the fashion of OLED, one LED per subpixel, as the name implies. That's in the lab today perhaps, not at Best Buy. The stated improvements for the 2017 Samsungs in the display itself is a brighter backlight and some tweaks to the quantum dot material.