Re: AdSense Disabled-Invalid Activity?
"Invalid activity" includes things like content farming and keyword spamming -- in other words, the same sort of things that Google regards as black-hat SEO -- and anything that triggers their "shady content" detector is going to affect your AdSense rating.
Keep in mind that Google's customers are the advertisers, not web users or content creators (you're the product they're selling) and that for programs like AdWords they do have a responsibility to their customers to ensure that targeted ads are seen by targeted users. That applies both to the advertising itself, and to search (if Google's search results drop too much in quality, they lose users, which means that their search results page AdWords lose value to their customers). Anything that even smells like it's inorganic (content created specifically to attract high-ticket/high-bid AdWords) occurring on a regular basis will eventually get your account nuked, and getting off of the bad-boy list at Google isn't even close to easy -- you would need to demonstrate a conspicuous and sustained change to what could be considered high-quality content (value-added or original and transparent* content not using spammy SEO techniques). If you fall afoul of Panda or are hit too many times with the Chrome Personal Block List extension, you're going to be spanked.
* Transparent in the sense that there is no difference between what the Google bot sees and what the end-user sees.
“Beware of bugs in the above code; I have only proved it correct, not tried it.” --Donald Knuth
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