Here's the official recording of Roger Willcocks speaking at Magento Live in 2013.
His theme was how to use Google Analytics to:
-understand & segment sources of traffic
-analyse mobile traffic
-where people land and where they go
-increase engagement/reduce bounce rates
-make navigation and search more effective
-understand checkout effectiveness
-reduce abandonment rates
Generally, 20 or so great ideas about how to use Google Analytics to improve sales and conversions on a Magento website.