Hello,
The EasySocial K2 app (possibly Joomla article, EasyBlog, EasyDiscuss too - untested) have an important problem. They stream content as well as item titles to the EasySocial stream, which is a nice, but if the items themselves are not public, the content is still displayed in the stream. This is true for sure for the K2 App. I worked with Nick to hack the K2 app so that at least we can hide the content as an option in the app config:
http://stackideas.com/forums/k2-app
So either I feel it should be a universal option to toggle content appearance in the stream off, or better yet to show titles only if the user has incorrect ACL permissions but show title AND content to those who have correct permissions. Note, the current option to limit display of content to a certain number of characters does not work if you select 'Limited' and use '0' for the value.
Jordan