http://www.cineplex.com/Movie/ghostbusters Nothing listed on Cineplex for show times yet, but I have been talking to the manager of the Chinook location in Calgary and she says most times she doesn't know unit the Tuesday before. She says because it is on for a week and not a special 1 or 2 shows, it falls into their regular show times. She does think the big 5, Vancouver, Calgary, Edmonton, Toronto (Montreal I think was the 5th) should have screenings.
I keep regularly checking this link for updates, and she told me she would call if she finds out sooner. Doesn't help you in Toronto, but maybe you can get a hold of a theater there. We are making an appearance in costume and I already cleared that with the managers. The 501st do it all the time there so they are used to it.