Many universities use Drupal
More and more universities start to embrace Drupal by moving departmental sites to Drupal. It is an emerging trend, and one that bodes well for Drupal. A lot of students are being introduced to Drupal this way.
Also, having worked at a university myself, I can say that universities are complex enterprises that often employ thousands of people. To me, these are important signs that Drupal is gaining momentum in the enterprise.
Paul Albert of Cornell University shared a great presentation that compares Drupal to Fatwire (a proprietary, enterprise WCMS), and that provides an excellent overview of how other universities are using Drupal.
If you want to bring Drupal into your enterprise, you should watch the video of Paul's presentation below. Highly recommended!