Originally Posted by
CMK10
I've had the opposite experience of the OP. Ever since United started ordering more 737-800s/900s and picking up used A-319s they've been putting mainline onto routes that didn't used to have it. RDU-IAD/EWR/ORD for example has a much better shot at mainline now than it did five or six years ago. The same can be said for EWR-IAD which was all Express until recently.
Delta is similar ever since they bought so many 717-200s. Even tertiary cities get mainline now (AVL/FAY/GSO-ATL etc.).
That's all quite true, and progress in the right direction, but those are routes that should never have been regionals in the first place. Those are solidly mainline routes. DL is sort of on and off. They have gone through phases as to which mainline routes are served with mainline craft, and which are not.