Via Extremetech:

The beta is confirmed to be running natively at 792p, and it seems unlikely that the final version of the game will be capable of running natively at 1080p on Microsoft’s console.

Respawn Entertainment’s Abbie Heppe recently confirmed the beta’s oddball native resolution, and the reactions have been mixed. On one hand, this is good news. Rumors were spreading that Titanfall could end up running at 720p, so this is a step up. On the other hand, the dream of running at 1080p on the Xbox One seems dead at this point. Even with the 53Mhz GPU bump and additional power gained by disabling the Kinect’s video features, a make-or-break game like Titanfall still can’t achieve 1080p.

"Next Gen" isn't living up to the hype.