Seems a waste of pixels to me. The 16x9 (1.78:1) ratio was chosen as a compermise between the normal 4:3(1.33) ratio, the sometimes used film ratio of 1.85:1 known as "widescreen"and the 2.35/2.40:1 ratio for modern 35mm film.
All the DTV standards for broadcast use 1.78:1 as does until now, all HDTV's because you can either letterbox or pillarbox TV or Film content and use the majority of pixels easily.
Maybe if they had decided on a 1.85:1 ratio so as to cater more to film and have only small pillarbox for 1.78:1 material, I could see the benefit.
The problem is that films do not always use a fixed ratio and all other content will either be scaled or pillarboxed yo loose much of the everyday benefit of the added pixels.
Beyond that, most anyone needing or wanting to see a film in the original aspect willl be using a projector and anamorphic lens along with som form of matte for the different movies and tv they watch rather than having pixels going unused or dealing with a distorted picture.