In defense of Arriva, I like it because of what it represents - a very large tower outside of the downtown core, in an area that's needed revitalization for decades. The area around the Saddledome was one of the scariest parts of Calgary not too many years ago, and soon it's going to be one of the nicest.
I realize this thread is intended to be strictly about the building itself, but I think the role a building plays in a community is as important as the architecture. Yes, Arriva isn't the first in that area, but it's certainly the nicest so far. And it's so damned TALL.