Oh c'mon Multi, not like you were planning on purchasing a European car as it is! ;)
Benz supposedly will have an exterior airbag inflating out of the front grille on the new upcoming S-Class. Will have to see footage of how that works, and how it can possibly sense objects hitting in time to protect.
The rules call for 'X' amount of inches between the hood and the hard components of the engine (around 2-4" or something). I take it the airbag housing or what-have-you would be allowed to take up that spot (@having less space for the engine). Of course, they could just develop even more compact, harder-to-service engines and keep the height of the hood similar to what it is now.
Hmmmm... perhaps we'll see more engines like those in the old Mazda MX-3 Precidia - an ultra-compact 1.8L 128hp V6.