I have installed SharePoint SP1 on my development machine. Yammer and OneDrive links have appeared in the Central Administration: If you go ahead and click “Configure Yammer”, you can activate it: Because: Yammer is Microsoft’s recommended tool for social collaboration. When you activate Yammer, you’ll get this dialog, and the Yammer link in the SuiteBar: What happens when you click on Yammer, is that you are redirected to Yammer.com and you are prompted a login page.

Ziegler provides a cool intro, implementation sample and much more. When deployed we can apply this policy to a contenttype in the UI, or in code. To create our own expiration logic we have to implement IExpirationFormula and its ComputeExpireDate: public class TaskExpiration : IExpirationFormula { public DateTime? ComputeExpireDate(SPListItem item, XmlNode parametersData) { if (!item\["Status"\].Equals("Completed")) { return null; } var dt = (DateTime) item\["Modified"\]; return dt.AddDays(30); } } ```In order to see IExpirationFormula, add a reference to Microsoft.