So wouldn't it be cool to have an option to open a 2nd Screen and define what was on it on your 2nd monitor?
Like, out of combat, I would want to use my Map view all of the time especially in dungeons where I tend to get lost and require lots of bringing my Map screen up and down up and down every 10 seconds. It would one annoying headache for me in that regard, and be very fun to have that second in-game screen, too! But now, in combat situation, I'd like that screen to switch to my potions and spells, sort of a split-screen view with the top half of my 2nd monitor all spells with a slider, and the bottom half all of my potions with a slider. And now, since my interface is always open, combat could be real-time for those with such monitor support. You could quickly fling your mouse across to monitor #2, click on a potion, and then re-engage combat on screen #1. Or, if no one likes the real-time idea, when your mouse crosses the threshold onto your 2nd screen, your first screen pauses and when you bring it back, it unpauses.
Either way, it makes for some new and interesting in-game choices for how to arrange and play your game.