I was looking for a nice way to implement Google AdSense, well, I looked through about 6 of them, and found my favorite.
Quick AdSense by TechMilieu! www.techmilieu.com/quick-adsense
The guys at Quick AdSense are not giving me anything, nor do they know I am posting this. I just wanted to say what my favorite AdSense implementation plugin for WordPress was.
It allows you to easily put ads where you want, how you want. I especially loved the ease of widget use. I have it running on my site now, see for yourself!