AdSense preview tool

Why do the ads differ before and after code insertion?

[UserFriendly]

Has anyone else found that the Google AdSense Preview Tool shows highly relevant ads before AdSense code is present on that page, but once AdSense code is actually on the page the ads become very different?

The preview had been showing me very relevant ads that seemed to obey the section targeting blocks that I'd used in the page. Once the actual AdSense had been inserted, though, the ads on the page seemingly began to disregard the section targeting blocks. And the preview tool now shows a raft of unwanted ad topics.

Any idea what's going on? Why does relevancy drop once you insert the code onto your page?

[UserFriendly]

Has no one else noticed this effect?

[AdSenseAdvisor]

This is certainly possible. AdSense uses a different crawler than the Google search engine. Once you insert the AdSense code on your page, it triggers our crawler to index your page content. Once you insert the code, your site gets crawled and the preview tool is more accurate.

[netmeg]

Yes, I've seen this behavior - I've also seen ads on my page that don't show up in the Preview tool for some reason - even though I'm sitting there looking at them while I pop-up the tool. As with everything, it's not 100% reliable, but better than nothing.

(I wish it would just pop up the domains rather than all the other trailing crap - usually I want to block the entire domain, so I'd like to be able to just cut and paste everything before AND after it.)

[UserFriendly]

Any suggestions as to why the section targeting seems to be ignored?