It's unfortunate but VIA will have to do more than just giving out a discount coupon every now and again to entice passengers to get on board to see this great country of ours.
That's certainly true for cross-country trips, but I find nothing beats Via Rail for shorter trips (4-6 hours each way) between Montreal and Toronto or Montreal and Quebec City. Both of those routes are interminably boring drives, and flying doesn't save much time over the train when you consider the time getting to the airport, waiting for the plane, and then landing at the airport outside of town and traveling from the airport to downtown.
I love taking the train to Toronto; I arrive relaxed and fresh, and can usually get a lot of work done en route if I'm traveling on business (although I find trying to type or select text for editing in a swaying train is just as hard as trying to type on an airplane in turbulence). The trains have WiFi, although you have to pay for it so I don't bother unless I truly have to be online.
I've taken the train from Montreal to Toronto and back about 10 times so far, and have never experienced delays or other problems -- it's far better than Amtrak in the States.