Google just released a new product - Google Analytics. It is not a new product per se - AdWords publishers had access to this tool earlier - but now it is released to the common public. This is a site that will analyze traffic to a site and display it to the user in a graphical and friendly way.
I have used many traffic logging sites in the past for my website Bin-Co. This softwares include StatCounter, eXtream Tracker, SiteMeter etc. But being free softwares, they had their restrictions - for example, StatCounter will log the details of only the last ten visitors. eXtream Tracker don't log nearly as much information about the visitors as StatCounter does. They all have their own benefits and their own disadvantages.
Now that Google have stepped into the field, things will start to change. The only restriction I have heard about their software is that they allow only sites will less than five million hits per month - and that is still a long way for my site.
But even now the best way to analyse your traffic is referral logs created by your server. Lets see if Google can beat that with its latest offering.