The B717, appears to be a good replacement for the DC9-30 aircraft, but in todays finance driven airline industry, it doesn't make economic sense for airlines to buy it. The reason is commonality, I know Boeing tried to distinguish it from the B737-500 etc, but when it comes down to it, it carries roughly the same amount of people. So even with lower operating costs, the costs saved by airlines in cross training crews on several types of B737's compared to just having them trained on one B717 type are greater. The new A318 just launched by Airbus has the same financial favour going for it, it may have a heavier operating weight, but with cockpit commonality with the A320 family, it will do better. Thus unless Boeing can produce several varients soon, it could be a white elephant!!!
Aircraft I've flown: A300/A310/A320/A321/A330/A340/B727/B732/B733/B734/B735/B738/B741/B742/B744/DC10/MD80/IL62/Bae146/AR