The BBC had a demo of the Olympics in 8k(7680 × 4320) with 22.2 sound, which I got to see in Glasgow.
The picture was amazing on the 15m screen, not quite like being in the crowd more like being in the corporate box with glass between.
The sound was what I thought was the stand-out, when the crowd were cheering and clapping it was like being there. Not sure how I'd fit 24 speakers in my place though.
The BBC demo was using according to the leaflet I picked up 330 megabits per second.