When I implemented Google AdSense I noticed my pages loading slower. This was to be somewhat expected, but pages were stopping while each ad loaded. The sidebar was especially slow to appear.
I decided that the best solution would be to load the ads in the footer, but I was a little nervous about how best to achieve this. Luckily, I found a great tutorial on building an AdSense loader. I had to make a few tweaks to the jQuery, but it was a great starting point.
I explained in an earlier post how to display multiple AdSense ads in the loop using WP_Query properties. This builds on that functionality.