I am running some websites and am constantly checking keywords' rankings on google.com. And it is really important for us to see the organic search result without logging in or setting a specific location. Since this morning my colleague and I have checked the same ranking on both IE and Firefox, the result surprisingly is very different (it almost feel like IE was logged in because the ranking is much higher, while in reality it is not). I have changed computer and the same problem occurred. It did not happen before. Can anyone tell me why is it?