the original thread was archived...too bad....as it was an interesting discussion....just died during the holidays and all of the recent news 787,747-8,A400 development/flight tests.
How Much More Evolved Will The 737 Become? (by C5LOAD Oct 26 2009 in Civil Aviation)

Found an interesting article today about the CFM56-7E (evolution) process.... compliments flight global:

"The CFM56-7BE engine has 9% fewer aerofoils as well as reshaped blades and vanes in the high- and low-pressure turbines to increase airflow through the engine and reduce operating temperatures. Combined with Boeing-designed modifications to the engine nozzle and plug, the engine will deliver 1% improvement in specific fuel consumption and 4% less maintenance costs. For the airframe in total, Boeing is advertising a 2% decrease in fuel consumption.

Boeing programs director at CFM Kris Shepherd says engineers are "trying to overshoot" the 1% target for the engine "a little bit to get some margin". In-flight data on the new engine will be available soon, as CFM 50/50 partner GE plans to begin flying a prototype on its 747-100 testbed in the US in February. Tests are expected to be complete in March, after which Boeing will begin testing the -7BE for the US Navy's P-8A Poseidon application, a variant of the Boeing 737-800."

What is of interest is the article discussed Airbus interest in similar modifcations for the CFM56-5B core that powers the A320. Signs that both manufactures will continue to 'evolve' their narrowbody platforms, rather than launch entirely new plane anytime soon.