I'm personally excited about the possibility of creating an "Emergency Card" (http://www.apple.com/ios/ios8/health/) that's accessible from the lock screen.
Currently, I use a screen-shotted contact screen as my wallpaper for my ICE contact - just in case the worst were to happen. This will let me put more information, and might even let me have a wallpaper again!
On the one side, yes; on the other, I doubt people will look at your phone in case of emergency. That is, at the moment - I guess it's quite possible this feature will change that. But that's a generation thing. Still best to have one of those medical bracelets with your blood type and allergies and the like.
Currently, I use a screen-shotted contact screen as my wallpaper for my ICE contact - just in case the worst were to happen. This will let me put more information, and might even let me have a wallpaper again!