I like the shape of it. The top is shaped like a square, and the bottom is shaped like a square, but the building ends up having eight sides because of the way it tapers.
Daniel Libeskind was the original architect for the building, but he was eventually forced to collaborate with David Childs. It was probably for the best, I've seen what happens when Libeskind is left to his own devices. Libeskind is a deconstructivist, so most of his designs tend to be rather bizarre; his design for the Jewish Museum in Berlin is one of the strangest things I've ever seen:
Jesus. Can you imagine being in one of the surrounding buildings and having to look at that god-awful shitty mess all day?