Tim Tucker (at the Airlie Beach Safety Course) said the new blades had stainless steel skin. All else was the same and if I recall correctly he said the weight was the same. The problem it leads to is that the skin has to be thinner to allow for the weight factor.
The skin will be more fragile. Even th R44 skin is surprizingly fragile. They had a section of blade at the course and the lecturer gave it a sharp tap with his knuckle which left a dent easily visibly in the surface.
So it will be a case of gain something and lose something else.