I whould probably digest this a bit more before commenting but my first thoughts are - in no particular order:
There is a concept of zones in the scoop ad system already. This would be suitable for sections and topics as they're limited in number and they're directly related to site architecture. The attributes country and keywords need to be tied to each ad submitted. While wer'e thinking about ways to enhance the ad system we need to implement CPC advertising as a site option. keywords really work best in the CPC world anyway. If we really wanted ot be leet, we could implement keyword pricing similar to that of Google, except our pricing would have to be related to either the frequency of occurence of the given keyword across all the stories in the scoop DB at the time, or, - and this may be far cooler - based on a cron based analysis of search engine referrer strings, to determine what keywords deliver users to our site.
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