Pubmatic just launched today. It's a new advertising platform, that optimizes your campaigns by using different ad networks, which compete with each other. The system is setup to show the ads that work the best for you. Pubmatic will even change the colors of your contextual advertising in order to improve your
income. A small presentation on how it works can be found here:
[flash] http://www.youtube.com/watch?v=sVW4Pwvtc7c [/flash]
The system looks very innovative and is certainly a great idea. Still for small publishers it most probably won't really work (at this stage), b/c the current ad
networks, that work with Pubmartic, need a minimum amount of traffic from your site. I also miss a few advertising/affiliate networks e.g. Auctionads, CJ, Linkshare, Contentlink....
Having said that, PubMatic is a startup that you should watch closely. It might have the ability to increase your advertising dollars significantly.