I have been evaluating Joomla (also planning to spend sometime with drupal) from some time for my personal website..
For my Team website at work, I have been working with Microsoft's Sharepoint product, and would say, its awesome!!! Creating whole site in sharepoint and managing/administrating it is so simple and yet effective. Workflow management feature is my favorite from the product suite.
I agree, Microsoft doesnt give it free, but its worth buying for enterprises. Its seamless integration with exchange and office system is also good enough.
Microsoft, YOU rock, yes, WE rock !!
Keep tuned.. 