Below is a video demonstration of some of Quad's main features.
Cisco is also integrating its Show and Share video technology into Quad, so users can quickly and easily post video. And there are APIs for integrating functionality via widgets. Cisco talked about integrating Salesforce, or project management. All of this will extend to the iPhone and the iPad, and, naturally, Cisco's Cius when it ships (this is the Cisco tablet).
If you're curious about Cisco Quad (re: what is it, how does it work, what can it integrate with, and what the user experience is like), watch the above video and read the entire story at Information Week. Anther good overview article can be found on TMCnet blogs: "Cisco Quad Points To Communications Future"