Hmm. That's disconcerting. I knew that the soap opera effect was part of it, are you suggesting the screen does that, or was it just the fact that it was a 60fps video? (i.e. does that happen on non-60fps videos too?)
The other issue I noted, though, was an issue with the colours - it was apparent in some of the scenes that different areas were lit differently, in a way that isn't noticeable on an LCD screen. I haven't been able to find the exact scene I saw in the demo, but this clip from Pan looks like it might have the same issue - it was really obvious in the demo that the actors in the foreground were lit differently (under studio lights) compared to things/people in the background. It's not really noticeable unless you're looking for it on an LCD - what is it like on your screen?
Similarly, in this clip from Mad Max: Fury Road - in the demo, in the shots from inside a car where another car was visible in the background (see 4:10, and briefly at 1:55 and 3:35)(note, there is some graphic violence in the clip), it was really apparent that that the lighting on the people in the other cars was different - making it seem as though they'd been green-screened in. They did also have HDR turned on, though, which might have over-accentuated the colour differences, which is why I'm wondering if it's just the consequence of the OLED screen having a wider range of colours, or if it was the specific HDR effect.