The committee building the 2008 revision of the main Cornell Library web site chose Drupal after evaluating several other options for source code control systems. There is not much documentation of the early stages of the decision making process. It takes a long time to evaluate these systems, and there wasn't much of it. Several other options were considered early on, but there was only time to concentrate on a few with high potential.
Here are some notes from the CUL Webvision Committee's decision process:
Minutes of Nov 16, 2007 meeting
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