I agree, I think google looks at a persons search patterns. For example if you were looking for, lets say ringtones, there is a good possibility that you would click a lot of ads that relate to ringtones in a short period of time. -HM
Google would never reveal how they determine it, as obviously that would lead to many people trying to abuse it and escape. Cookies do get used so google can track 30days at least...(think it is a 30 day cookie) ... but with them also having the toolbar and other things, it enables them to compile browsing styles and such like. When everything is evaluated, even if it was all legitimate, Google can still ban people at their discretion
Haha, you didn't have to reply then Anyhow, one can only guess - no one knows for sure, except Google.