New Boeing 737 Vs. New Airbus A320: Who will prevail?

Boeing to build 737 replacement: CEO | Wichita Business Journal: "If Boeing builds a new single-aisle aircraft to replace the 737, as now seems increasingly likely, the key to that decision may be the substantial weight reductions obtainable with lighter materials."
In a related matter 'Boeing patent may provide glimpse into 737 replacement plan'
 Boeing engineers Mithra Sankrithi and Kevin Retz. Retz and Sankrithi have come up with several methods of developing a composite fuselage design to accommodate a seven-abreast 2-3-2 twin-aisle configuration ideal for quick loading of passengers and cargo.