Absolutely - OLED is really needed to make the most of HDR - it has a much better dynamic range and really good blacks. A friend has the LG55" Ultra HD and the sense of 3D is amazing simply because of the visual clues you get from the definition and dynamic range - and without the artificiality the stereoscopic 3D introduced.
It would be the TV I would buy if I had the space (but not to watch the world cup thingy on - which I won't be watching on anything!)