Among other new social features in SharePoint 2010, users are now able to rate items in lists and libraries to help their peers find the most relevant content on the site.
Unless your SharePoint portal is a brand new implementation, the social rating feature will need to be enabled manually on each library before users can work with it.
One alternative is for users to enable the feature manually. However, for this to happen, your users require higher-level access to the site. An alternative is for the administrator to enable the feature in multiple libraries of the SharePoint user interface, and PowerShell can help with that. Additionally, during a disaster recovery of your site, it will be much simpler and faster to restore this configuration rather than leaving it to be manually implemented.
Assuming you have already set up your virtual development environment as described in Chapter 1, PowerShell Scripting Methods and Creating...