I think you can see at least a glimpse of the future of online marketing and the relationship that search engines can play by simply taking a look at Searchking.com
The searchers "vote" on relevant sites. There is a forum for website promoters discussing the ins and outs of how the engine works. You can edit your listing instantly. You can bid on locked in keyword banners starting at about $5 a month AND you can edit those instantly too. Now anyone with an online mall or a limited time offer or a limited quantity product can change there ad daily. This alone will open a whole new arena of online marketing.