That definitely is a cool feature. More tablets should follow their lead.
Yup I agree that's a great first step. However, it would still be awesome if the controller was integrated so that you wouldn't have to bring a controller everywhere you go. You have to go places with the forethought that you may play games. It should be easier than that!
The Shield does look cool, but I'm worried that games that will take advantage of it are few and far between. Hopefully that will change.