will write more about this in a bit... found this via Bill Flitter (a former fellow Wisconsinite, and UW-Oshkosh Alumnus) of Pheedo - great stuff they're doing over there!

http://bobwyman.pubsub.com/main/2004/02/publishsubscrib.html
The publish-subscribe service has a number of unique aspects that can make advertising more effective and more responsive to user needs and desires:

1. Because responses to subscriptions and the ads in them are more likely to be relevant to user needs, publish-subscribe services can afford to place fewer ads in each unit of content delivered.
2. Because publish/subscribe services provide tools that allow great precision in searches and ensure that the user is in control of the content they receive, it becomes possible to think of "ads as content.
3. Doing "branding" with banner ads, etc. has proven difficult.
4. PubSub content is typically delivered a message at a time rather than as a list of results.
5. Publish/Subscribe services, because they have persistent lists of subscriptions, can provide precise predications as to how many people will see any particular ad as well as how many people are likely to see any particular content with which an ad might be associated. Thus, it becomes possible for advertisers to have much more effective tools for budgeting and planning their campaigns.