I think FlyerGoldII has a point for routes between Toronto-Ottawa and Montreal, where the fastest train is approx 4+ hrs downtown to downtown with much improved WiFi which is comparable to flying + check in + getting transportation into/out of downtown.
VIA's got several fares..... In Economy there's Escape from $49, Their 50% off stuff $69 onwards and at times 75% off last minute fares at $59.........