A couple of years ago, I decided to ride this line since it had been a very long time (since 1970!) since I'd gone this way (on CN's Super Continental), and I could also ride Ottawa-Toronto on the ex-CP line via Brockville (which I had never done).
I rode a set of stainless steel cars out of Montreal, and was surprised to see all the trackwork and the new signals. I confirmed the line is now owned and dispatched by VIA, and (except for the at-grade crossing with CP shortly after leaving Coteau) is quite fast.
I continued on an LRC train from Toronto, and my notes describe the single track to Brockville as "alarmingly fast", at least 90 MPH, right across grade crossings. The LRC equipment tends to roll quite a bit, and I found that a bit disturbing. The line out of Ottawa is actually ex-CN to Smith's Falls, where VIA has a new connection to the CP main, then the train turns off onto the Brockville line, which is also being re-signaled. I was last over the CN portion on the overnight Ottawa-Toronto train in 1969 (it ran to Nappanee over a now-abandoned CNoR line). It's much faster too. The CP Smiths Falls to Brockville was new to me; the "main line" from Brockville to Toronto was not.
It was an interesting trip. VIA's "corridor" is a long way from the NEC, but not a bad service, and well patronized.
Randy Resor, aka "NellieBly" passed away on November 1, 2013. We honor his memory and his devotion to railroading at railroad.net.