When Microsoft Dynamics CRM 2013 is integrated with Yammer, data feeds are available to users of Yammer either natively in Yammer.com or via Dynamics CRM 2013 directly. If you plan to use Yammer with Microsoft Dynamics CRM 2013, keep the following in mind:
The free edition of Yammer does not work with Dynamics CRM 2013.
Activity feeds and Yammer are incompatible. Once you install Yammer, activity feeds (and their data) are available only programmatically.
User conversations are stored in Yammer, not in Microsoft Dynamics ...