For starters, the site is packed with an inordinate amount of information. Here's the homepage for the School of information.

And while the site is a bit busy, the site is laid out well enough that everything is easily findable, searchable, and navigable. Don't know if all those "able" words are words, but you get the idea.
It is much easier to mess up a site displaying this much information than it is to pull it off well.
And for each of the items on the navigation bar, which runs horizontally across the screen, there is an elegant menu that pops up when you hover over the item. The menu for the MSI link looks like the one under the MSI Degree button:

The Ph.D page is packed, but designed well, and while it breaks the rule that says users don't like to read, so put less text up there, the audience for this page is different than most. The audience for this site demands detailed information, and the site provides it.

I especially like the consistency in the Navigation bars at the top, bottom, and left of the page.
My only real problem is that you can tell when the page has been updated, but it's difficult to tell what new content has been added.