Originally Posted by MadisonAvenue

It's just an all around good idea to never put all your eggs in one basket. As a Publisher you should be using an ad rotation system that enables you to juggle many different ad networks (adbrite/avn/etology/aaw/etc) and determine which ones generate the highest RPM (rev/1000 impressions) for you.

Back when I was running SickSiteNetwork we took it a step further and sliced our traffic in such a way that we sent some out on affiliate basis (CPA/RevShare), sold some on retail basis (CPC/CPM), and sent some to the ad networks.

As an Advertiser you should look at Traffic Sources like the stock market game: always keep a balanced portfolio. Even the best Traffic Sources dry up or get overexposed. You should also never put up with sub-standard service. Finally you should READ THE TERMS AND CONDITIONS. Ever read adbrite's? They actually say they're not promising you any specific number of clicks or impressions.