14 DAY TRIAL // The Google Groups Forum are always the best place to gather interesting pieces of information about the product you're using in case it's designed by the Mountain View based company. Many people have found relief and answers to their problems there and that's to say Google is currently trying to improve the Public Relations Department quality and response time.
The item I'm referring to has had its share of rough times and waiting, but yesterday had Jeff Posnick, an AdWords API Advisor, shed some light on it: An ad run through AdWords, if edited, changes and technically becomes a new add, as "rustybrick" of seroundtable.com put it.
"If you've ever edited an ad via the AdWords web interface and you're particularly inquisitive, you might notice that the ad's underlying ID changes after the update. You also might notice that there's a running count of how many "edited or deleted" ads there are in the Ad Variations tab of a given ad group in the web interface. One might draw the conclusion from this that when you edit an ad's text via the AdWords web interface, you're effectively creating a new ad and disabling/deleting the previous ad, allowing our system to keep track of the previous ad versions with a unique ID as well as the current one," Posnick said.
When editing an ad, its ID is archived and a new one is created for the new one. Google doesn't quite see this as creating a new ad from scratch, (normally, I should think), but instead it shows a symbolic link between the original and the ad resulting from the modifications that have taken place. "rustybrick" mentions that "when edited an ad, it may not impact the quality score as much as starting a new ad." In case not everything is cleared up, you should go to the Google Groups forums and ask away. You'll most certainly not be ignored.