When I first heard the news, I dreaded the thought that it'd be something completely strange, like swinging your sword around to incorporate "cheap realism". However, when I watched the video, I found it to be quite nice to be able to command your followers with your voice.
Of course also the amazing feeling you surely will get from yelling a shout. Might gain you some weird looks from family, but who cares. You're the Dragonborn.
I've long thought that this is the best way to implement Kinect for core games and the commands for quick switching weapons, quick saving and of course the shouts look really impressive. I don't think I'll bother with the companion commands though...because I don't at the moment anyway. Just run Lydia...attack that thing!