As a new WordPress user one of the first things I did was install the WordPress.com stats plugin. However, I was disappointed at the depth of information that it provides. I was fortunate enough to discover Statcounter.com when I first started designing sites almost 4 years ago, and continue to be impressed by the free service they offer. I’ve now installed the Statcounter WordPress plugin on this blog and found it straightforward and simple.
I have investigated Google Analytics and am currently using it on a couple of sites. If you are contemplating running an Adwords advertisement and marketing campaign I would highly recommend it. There are currently over 80 distinct reports, each customizable to some degree, and users can see ad group and keyword performance as part of their reports. The ability it offers users to define and track conversions, or goals, such as sales, lead generation, viewing a specific page, or downloading a particular file undoubtably prove invaluable under certain circumstances, particularly for e-Commerce applications.
For my purposes however, and at this time, Statcounter seems to provide the better solution.