The story of 7-11 in Japan (part of The Economist's e-commerce case study series) is really a story about business intelligence and the power of real-time analytics. According to the article, new technology that 7-11 adopted in the mid 1990's provided four benefits:
The first was in monitoring customer needs, which were changing as deregulation made shoppers more demanding...
...Second, Seven-Eleven uses sales data and software to improve quality control, pricing and product development. Thanks to its systems, the company can collect sales information from all its stores three times a day, and analyse it in roughly 20 minutes....
...Third, technology has helped to predict daily trends. As customers become more fickle, product cycles are shortening. Fashions in boxed lunches, riceballs and sandwiches, which make up almost half of a convenience store’s daily sales, are especially short-term. Most last about seven weeks, but they can be even shorter...
Finally, Seven-Eleven’s electronic investment has also improved the efficiency of its supply chain. Orders flow quickly.

Interestingly, only the fourth benefit actually relates to e-commerce. The rest are about using data more efficiently to make effective business decisions.
One of the most innovative parts of the system is not the technology used, but a unique way of putting disparate data together to come up with something completely new:
Seven-Eleven says it can keep abreast of these partly by keeping an eye on the weather. Five reports a day arrive electronically at its stores from hundreds of private weather centres, each covering a radius of 20km (13 miles). This is useful in Japan, where temperatures between towns 40km apart can vary by as much as 5C. The reports also compare today’s temperature with yesterday’s. “The same 10C can feel very different depending on whether it was 1C or 20C the day before. This is critical for predicting food purchases,” points out Mr Usui.