Joined: 09 May 10
25 Jul 10 10:01 pm
There is a QS at the keyword, adgroup, campaign, account, and domain level (and probably more!). I don't know much about the Content Network, but I wouldn't be surprised that the QS gained from your Google Search campaigns is going to be factored in.
Also... there might be much less Ad positions available on a page in the Content Network than in the Google SERP.