There will be an Open Source CMS Summit this Spring (March 22nd and 23rd) at Yahoo headquarters in Sunnyvale, CA. The Drupal project is spearheading it but all other projects are invited to participate. With the decline of OSCOM, it is nice to see these kind of events happening. Project teams learn from other projects' strengths and experiences. Most of the current proposals are about Drupal and Munwar Shariff is also planning to talk about Alfresco (He just published an Alfresco book. Review from me coming soon).
You might remember Drupal and eZ publish put on a similar conference in Vancouver last year. I found out about it pretty late, as did the general OSCOM community that was battling inertia of organizing a conference of their own. I heard it was a great time.