Not much of an aviation expert, but will this be a better alternative for airlines than the new Airbus behemoth that doesn’t even work right?
Boeing will respond at some point after the 787 gets going with a larger 747 in a similar way that they did with the 737-800 (Really a new airplane flying under the type certificate of the existing airframe... Which Airbus REALLY hates.).
I’d say in 5-7 years the 747x (650-750 passengers) will resurface as more airport infrastructure is built to handle the larger aircraft.
After that, Boeing will have the kinks worked out of their cargo variant of a blended wing-body aircraft. Say in 10-15 years expect an aircraft that can haul 1,000 people, yet able to fit into the infrastructure of a 747...
Well, there are several 380's flying, and are route qualified on most routes early delivery customers will use.
If that's not working, I don't know what is.
As for composites, it wasn't long ago that the Airbus bashers were throwing a fit about it's use of composites, and praising Boeing for not.
They have completely reversed their positions now, convinced that composites are wonderfuuullll.