For the past month I have had Google's Analytical code up by my header instead of the footer. I expected a few more visitors, and a higher bounce rate. I did this because I am always reading it can make a big difference. I even saw one claim that in increased their numbers by 20%. My visitors did go up, but that is usually the case. Bounce actually went down though, so I really saw no difference in positioning. I tried slicing and dicing my data if I could see any indicators, and nothing revealed itself. This was all based on thousands of visitors as well. Does moving the code up to the top give you better results? I don't think so, and if it does it won't be a significant change enough for you to even recognize. If you are loading javascript from other sites I would make sure they would load before G's. G's is far more dependable.