Me thinks Airbus is running straight into another A350(1st version) vs 787 debacle.
The A320NEO will get new engines, a new pylon, winglets and a few tweaks. Result up to 18% fuel saving. But, it is still the plain design from the mid 80s. Same old wing, same old systems architecture, same old materials.
The 797 will be an all-new plane. Same new engines as the NEO, but new wing, new materials, new aerodynamic set-up and all-new systems architecture derived from the 787. Resulst should be around 25% fuel saving.
Surely, Airbus got nice, and also large orders for the NEO. But they did not win a crucial customer. Not yet.
All the big guys in the game are waiting. UA, AA, DL, LH, each of them good for a 200+ aircraft order. And there is a reason why they wait. Why buy the second best solution with a 10% price add on the A320 when you can have a even more appealing product in 3-6 months?!?
The big question for Airbus will be: What happens when 500 NEO are sold and Boeing launches the 797 with massive orders from the big guys, reaching 1.000+ easily. Will they accept a 2:1 split on long time or will they - once again - be forced to follow with an own all new design.
At the end, it is well about this 7% that make the difference between 18% and 25%, but it is also about offering a totally new product with state-of-the-art technology. And exactly that is what all the big customers demand. A state-of-the-art new plane, with new materials, new wings, new engines and a substancial fuel-burn reduction.