Roger Willcocks spoke recently at Magento Live 2013, in London.
The talk discussed how retailers should go about using Google Analytics to measure site sales and conversion performance. Magento's own summary reads thus: "Screen Pages’ Roger Wilcocks offered practical advice on tracking key metrics and shared insightful benchmarks across 100+ stores. Key takeaways include focusing your plan around the behaviors that influence conversion, keeping a keen eye on what makes for a good proposition, as well as planning out your improvements with metric targets. At the end of the day, It’s all about measurement and refinement.
Here are the slides themselves: