Unfortunately I fear that there won't be any trijet any more
because of the maintenance difficulties envolved. I hope the 717 will be sold well and upgraded to a real familly, why not with a 717-400 which will permit boeing to get rid of the whole 737 familly ; I think the MD-90 is such a great plane!!! So Boeing won't need any 737-1000 anymore!!!
Concerning the Sonic Cruiser, I fear this was only a false alert to counter the A380 and that it will never fly because of much too high operational costs due to enormous fuel consumption for too few pax.