DP 1.3 would get us 4K @90Hz, but they need the connector to work on most of their consumer base.
With that in mind I feel we may end up with HDMI, since most laptops have that, and 1440p. 1440p is a good balance since it has a very low screen door effect, and laptop gamers can simply use 720p low quality settings and not have to worry about scaling, whereas people with beefier rigs can run @ native resolution, maybe with the settings turned down a bit, or a lot for AAA games.
My hope is simulating virtual reality will give everything a massive push - better hardware to hit the very high framerates required, and better audio to simulate the environment. Display tech needs to get better/cheaper, and I'd also quite like the ray-tracing chips Imagination revealed to be integrated into GPUs.
Edit: Oculus did say that single screen was easier. Ideally we could have something with a 2:1 aspect ratio (ish) since each eye could get a square screen (effectively).
A single screen also means you can avoid the pain of trying to sync the screens perfectly.
good point. they might offer a simple 'low' and 'high' setting then? That is if they do go higher than 1080p