not2easy - 4:30 am on Oct 31, 2013 (gmt 0)
The AdsBot is generally checking for content on landing pages to determine relevance and quality score. I block it on GP because I am not running AdWords.
Many years ago I found an empty WP site bouncing an Ad campaign off my content and decided that it was easier to deny AdsBot. I have no clue how they were doing it, but a Google alert led me to the site and when I couldn't see anything there I used the URL to "save file as" and saw a .php header redirect. I am not saying that is what is happening, but if you are not running AdWords, I would deny it in robots.txt