Absolutely fantastic, though it's definitely a long, long, long way from coming to pass. I hope they choose the approach recommended by the study in the mid-90s: 300+km/h trains on a separate right of way. The optimal routing is from Windsor to London on the existing CN line, with freight diverted to the busier CP route; from London to Kitchener on a new right-of-way; from Kitchener to Pearson on the existing right-of-way with a by-pass of Guelph; from Pearson to Union on the Weston Sub; from Union to about Oshawa on the Kingston Sub right-of-way; from Oshawa to Kingston on a new right-of-way north of the 401; from Kingston to Ottawa via a new route to Smiths Falls and the existing VIA-owned route north to Ottawa; from Ottawa to Montreal on the abandoned M&O Sub already owned by VIA for a potential high speed route; from Montreal to Quebec via Laval and Trois Rivieres on the existing former CP route. That's pretty much the route recommended in the mid-90s study.
High speed rail has enormous potential. It's absolutely bizarre how in countries all of the world, including all of Europe, high speed rail is considered economically and environmentally essential. The only places on earth where it's considered a frill are Anglo-Saxon countries. If nothing else, it will completely and forever eliminate the need to build a Pickering airport, saving billions of dollars and incalculable environmental impacts in the process. It would conveniently serve Trudeau and Pearson airports, allowing for convenient air-rail connections. High speed rail would serve many different markets. In addition to standard intercity travellers, the biggest traffic potential (as we have seen in Spain) comes from expanded commuting opportunities to big cities. If we build a real high-speed line, a huge amount of traffic will come from routes like Kitchener-Toronto and perhaps London-Toronto. It might even open up Ottawa-Montreal and Quebec-Montreal commuting.
It's absolutely insane that the home of the world's biggest manufacturer of high-speed trains doesn't have a single example of the type. The biggest danger is that Canada falls into the typical Anglo-Saxon trap of the "cheapo" solution (a term that Hipster Duck, I believe, coined a little while ago). It's absolutely hilarious to listen to people in England, for example, dismiss the notion of maglev trains because they're a new and unproven technology. Regardless of the problems and benefits of maglev, it's quite the contrast with their willingness to jump at completely unproven technologies like gas turbine engines and complex tilting systems. Risky new technologies are okay if the new technologies offer worse service than existing ones, but completely unacceptable if the service is potentially much better. Look at the disaster that is Acela Express, where the Americans tried to run a high-speed train on 1920s tracks and catenary. If we're going to build it, build it right. A 300km/h+ TGV-style technology that's been adopted all around the world. We should also at least look at Maglev, which anyone who's ever ridden it would say is extremely impressive, though with attendant risks.