I failed to see any noticeable difference by the panels (IPS Black by LGD vs previous gen IPS panel by BOE). Due to lighting condition and/or filming angle, the display on the left in the youtube's videos will _always_ appear better to me because it has less reflection. these comparison videos are helpful but with lot of limitation. People have to see in person.
My take-away was IPS Black panel has some improvement in contrast but offset by worse backlight implementation. I'm referring to 27UQ850 vs 27UP850 (which I spent some time research). That is BOE did a better job on the backlight in their panels. LGD didn't do as a good job in their IPS Black panels. Perhaps LGD will be able to improve backlight quality in future production batches. So far IPS Black + poorer backlight is a wash. If people see deep discount on previous generation, it'll be a steal.
I don't know if Dell U2723QE shares the essentially same backlight implementation as in LG U27UQ850. I made an incorrect statement in my previous post in this thread (which I'm going to correct it). U2723QE doesn't have hundreds of dimming zones. It only has _four_ dimming zones which give me the impression that essentially U2723QE and U27UQ850 share the same backlight implementation. Only a tiny software tweak that let the Dell have four zones. Pretty much useless selling point IMO.
If people cannot decide between Dell and LG, compare support, warranty service, power supply and other fringe benefits may help. If people cannot decide between IPS Black panel and BOE panels, you won't go wrong with the cheaper price options. Essentially both panels perform much similar than any difference overall.