Providing an online site has everything established for user friendly searching and ordering then certainly this beats the traditional running around and dealing with hoards of other shoppers. The discount coupons business appears to be booming on line.

I would like to know the percentage of population who is using online buying by product segment? Equally the transition rate from traditional to online is another interesting statistic that could support the retailers in their own development and change management from traditional to online. I am also interested to consider how our shopping centers may look like in the future and how this may affect town planning. What type of workforce will be required in the next generation? Just food for thought my friends.

As you say you could fire an event using your web analytics package and even capture the promo code for later examination. This way you will know what promo codes are failing and you can do something about it, especially if its business critical.

You may even decide to segment visitors by promo code (using custom _setVar() variables (in Google Analytics) for example. This would let you see the biggest revenue winners in terms of promo codes.

And it seems as though a lot of major retailers hold weekly or bi-weekly sales based on events.