Etsy started added a new tool for sellers last month. When you go to your "Your Account" page, there is a "Shop Stats" menu item that will open up a whole new world for you. Because it is new, you will only see stats back to the starting date.
You may think that you have the whole statistics thing covered by using Google Analytics, but Shop Stats offers you something that Google can't. Google Analytics can tell you how many visits to your shop came from Etsy.com. Shop Stats will tell you how many came from searches, treasuries, activity feeds, favorites, etc. Now you will be able to see if treasuries really do anything to promote your shop or how circles and activity feeds impact you. I was happy to see it broken down to show the number of people searching within my shop and even how many click on the category listings.
The overwhelming majority of people visiting my shop are coming from within Etsy, but at least now I will be able to see how they found me. I can also see how effective it has been to join linky parties and how many people have clicked on the shop widget on my blog.
Go check your Shop Stats and let us know what you discovered.