Are you referring to the Social Marketing add-on? I, too, posed this question to the community last year (https://community.marketo.com/MarketoDiscussionDetail?id=90650000000PwnHAAS). We're really struggling to get any value from this. Primarily due to the fact that there's no way to report across workspaces (we have 23 workspaces). We've also experienced a few bugs and the need to create a customized/branded page that will appear when an content is shared (see screenshot below). And finally, I'm learning that there are very few customers who opt for the "social boost & promotion" add-on and just use the social capabilities that come standard with Marketo.