In the world of web analytics competitive intelligence is probably the most under used technique. The web allows you to be able to conduct really good competitor research on your direct and indirect competitors, and the great thing about this type of data is that it is mostly available for free.
By using sites like compete.com you are able to gather data on your competitors such as how long your users spend on your site vs. theirs. You are able to also see things such as repeat visits, pageviews per user, web growth and so on.
Using competitive intelligence data is like opening your curtains and seeing where you live in your neighborhood, you can see what your house looks like compared to others around you.
Knowing how you are performing is good, knowing how you are performing against your competition is priceless, it not only helps you to improve, it helps you to identify new opportunities and help you to stay relevant.