First I heard of it. Looks interesting. Going to check it out a bit more. Thanks for the link.
Do you use it?

no, just saw that it had won an award. Apparently something it does really well is document management. The developers of CiviCRM used both it and Drupal when they created the Amnesty International site.

My understanding is that alfresco is a new it product. I don't know many details but I have heard good things.