A new video has surfaced that gives us a look at how the Xbox One dashboard will work -- specifically, it demonstrations how to "snap apps." What this does essentially is it allows you to have an app running on the side while you're playing a game, like Internet Explorer (for walkthroughs), or companion videos.
In the demonstration, the user switches between different apps like the Game DVR and IE, and snaps it to the side of the game he's playing (in this case, Battlefield 4). The key takeaway from this is that the entire UI is running very quickly, about on par with what Microsoft demonstrated back during E3. In particular, I really like how fast it feels to go back and forth between the game and the dashboard.