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I would definitely fancy a 30in display and wouldn't go any larger for as far as a computer display goes. I would also hope that it would be maybe an OLED monitor (one can only dream) but apart from that I also hope it will be a glass display, not some cheap-o plastic thing like what's already out there on the market.
 
at the demo for imac pro in new York and probably in their campus last week (i was on NY), from the discussion it will be an Apple pro display 8k 28-32" range
 
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