I have no experience with Drupal.
How does Drupal compare to SharePoint 2007 (or 2010) for the following “features”
- Document management
- Role and permission management
- Office integration
- Web Content management
- Custom server side development (features, custom pages, access to external data…)
- Deployment
Actually the main difference between Sharepoint and Drupal is that Sharepoint ships with certain features that you can barely change.
In contrary Drupal has lots of extensions which are open source, that you can change and fit to your needs. So, your question is a little general, it depends how you’re going to configure your Drupal, what modules you intend to use and so on….
In my opinion, Drupal can be very powerful but there is a little chaos in all the modules developed for it. Everybody can implement what features he feels is ok and in the end of the day the client-developer is staring at whole bunch of software wondering what to choose, what is better, how this works, etc ..
And back to your question, Drupal has all this features that Sharepoint has .. some are better implemented (like roles, permissions, and deployment) some not so good (office integration).