If you need to build a multilingual community based on Commons, you'll probably use entity translation to translate your content and not content translation.
Why? Think about groups or events, where you only want to have one node. Or machine-translated comments to enable multilingual discussions.
Therefore it would be a benefit to include the title module (http://drupal.org/project/title) in Commons and replace all titles with an entity field and take care of it in all views build so far.
This would make it smarter or enable multilingual communities to follow updates on Commons more easily. Otherwise each Commons update would result in a huge amount of rework.