Montreal for me. Vancouver has an amazing setting, but Montreal has the kind of North American big city look I like. Every view of the Calgary skyline I see seems to have some suburban housing or wide open area in the foreground. Edmonton and Hamilton look too communist (and Hamilton's is unbalanced). Winnipeg's not bad, but not big enough, London would be good but it's all spread out. It's hard for me to find anything to like about Mississauga, KW or Niagara Falls. Quebec is beautiful, but not because of its "skyline". Ottawa actually seems like somebody took a huge chainsaw and lopped the tops of all the buildings off. This is all just nitpicking though, most Canadian cities have decent skylines for their size.
Some different angles of Hamilton
I like the core of Hamilton much better than the skyline as a whole.