Jeff, Out of the 88.2%, how much of the traffic was previously browsing stackoverflow, then went to Google to run a search, then came back to stackoverflow? I know frequently when I'm looking for an answer to a question I use Google search rather than the stackoverflow search because it works well (for me) and I'm familiar with how Google behaves. I think the SO search probably works fine, but it's not what I'm familiar with. Also very often I don't know whether my I want to search stackoverflow or serverfault, so again Google works better. I know each site has it's intended audience/purpose, but very often there are nuggets of information that exist on the opposite site. By altering the "inurl:" parameter on Google I can quickly look at a particular site. Also, within the 88% aren't there people that Googled "stackoverflow" rather than typing it into the address bar? Technically Google would be the traffic source on these, but I wouldn't categorize them the same.