Why 5 stars? Because this is the cleanest airport I've ever seen.
--- --- ---
Much like all of Toronto that I saw, and I'm assuming the entire nation of Canada, the floors of this airport looked clean enough to eat off. Maybe it's not that Canadians are clean, but we're just slobs. For shame, fellow Americans!
Aside from the cleanliness, I enjoy the modern, sleek, and open feel of the terminal I arrived in. My stay in the airport was only long enough for me to get through customs, and head to the rental car area, but I was so impressed with the cleanliness, that I couldn't move forward in life without penning this review.