Add a Social Hub sidebar widget. This widget should collect all informations from popular social sites, like:
- Lotus Connections (profile, blog entry, etc)
When You click on a mail/calendar entry, this widget recognizes the sender email address and searches those sites for this user and lists posts. (as Outlook does this with FB)
There can be separate backend plugins for each social sites, those plugins can provide standardised (eg xml) input for the sidebar widget on the UI. So, independent developers can extend the widget with several other social (or other) sources.