>>48958Wow, field too long...
Now the two new designs are pushing new materials. The 380 uses glass fiber combined with aluminum, and has a design that wouldn't be feasible with the previous all aluminum fuselage. However, this is still sheet material, which makes it not practical for designs like BWB's which require double curvature.
Now the 787 uses carbon fiber, but the design is still very much alike the previous generations of aircraft. So we see a new material being applied to an old design, instead of making up a new design for it. This makes the development easier, and more predictable, which is important for a product like this. If they had chosen to change both elements, they would have had to start from scratch, and like the early designers making all metal airplanes, ended up in an inefficient design.
So now that a new material is being used, we might see (provided it will prove to be suitable) two changes: a gradual development of current designs (other types being replaced by 787 like designs, but with improved structures based on knowledge gained by the 787 development) and (after a while) a development towards new designs that make better use of the potential of carbon fiber, like BWB's.
Tl;dr: Blended Wings will be there, just wait.
Provided that the design proves to be more aerodynamically efficient, structures and processes will adapt to make it feasable. The material has already (is making, more correctly) the step towards it.
