I couldn't get that trailer to play. It took forever to download the first few seconds and the video froze constantly.
But it could be that video or the site itself. These two were the first 4k videos I found through a Google search and I was able to load them quickly and they played without any hiccups.
http://www.youtube.com/watch?v=k_okcNVZqqI&list=PLD33E5618740295DF&index=1
http://gizmodo.com/5994009/4k-video-at-1000-frames-per-second-will-melt-your-eyes
(Late 2012 27" iMac 3.4ghz i7)
But it could be that video or the site itself. These two were the first 4k videos I found through a Google search and I was able to load them quickly and they played without any hiccups.
http://www.youtube.com/watch?v=k_okcNVZqqI&list=PLD33E5618740295DF&index=1
http://gizmodo.com/5994009/4k-video-at-1000-frames-per-second-will-melt-your-eyes
(Late 2012 27" iMac 3.4ghz i7)