I don't think the bowl game will be well attended at all....and why should it be? We're getting a crappy, third-rate bowl game between two teams that will have limited or no appeal in the Toronto area. There will likely not be many American fans making the trip into town due to the passport requirement (although that may not be fully in place by then), not to mention the distance, cost and hassle of leaving their country. (and the weather).
This game makes no sense at all
sambo, you are right that TO fans are fickle, but there other factors to account for poor attendances at some of the events you listed. NFL exhibition games didn't draw well because they were just exhibition games (not many star players actually came or played). The Jays drop off was more a result of the season-ending strike in '94 and bad teams that followed that year than just a World Series hangover.