In my last article, I pointed out some of the changes that Google recently made to AdSense. I discussed how you can now put ad units on error, login, registration, thank you and welcome pages, and suggested that you might want to think about adding content to those pages to ensure that you received target ads.
The other significant change that Google introduced was to start tracking the keywords that users look for in the AdSense for Search boxes. Until now if you wanted to know what your users were looking for when they reached your site, you had go through a complicated workaround that involved creating a special logo then tracking that logo through your logs. The keywords that the user entered appear as part of the URL on which your logo was called.
Frankly, I found that just too much effort for the sort of returns that AdSense for Search brings on my sites but if it works for some people, good luck to them.