Do you know anything about KISSmetrics?
KISSmetrics is a really good tool if you want to gain insight into specific visitors, instead of visitors in aggregate or simple pageviews. It provides a lot of useful information into how a particular customer got to your website, what they did while browsing your website, the steps they took to make a purchase and even what happened after the sale.
Smaller retailers may find it a bit expensive or don't want to spend extra money when they already have Google Analytics. However, if you have a bigger website you may want to consider KISSmetrics because it provides some valuable insight into your customer's behavior that Google Analytics simply cannot provide.