It's a simple website that helps to prepare to Sitecore CMS update by displaying update steps and links to appropriate pages on SDN.
You just need to specify source / target versions, and click "Process".
The Sitecore Social Connected module contains several independent tools:
Social Connector allows website visitors to log in your website using credentials from their social network accounts. Your website receives more information about the visitor from the social network profile. You can use it to personalize the website.
Social Publishing allows posting automatic updates to the social networks along with publishing Sitecore items.
Putting Like and Tweet buttons on the webpage. You can put the buttons as Sitecore controls and track users' activity using Sitecore analytics.
The Search Engine Optimization module helps administrators to detect the missing pieces of content which influence the page rank and to make the content more search engine friendly. The module contains features for both the content editors and the web site developers.