[webmasterworld.com ]

I go back and forth, I might get 1% or 2% more with them on some days but most of the ads are poorly targeted for my niche so I suspect I lose as much or more some days too.

Right now I have them allowed but I don't allow animated images and I'm not getting any impressions from those networks. Earnings have gone up dramatically since I made that change, but it might just be coincidental.

I'm hesitating to block them because Google is telling me I'll earn more If I allow them:

"Google certified ad networks may be notified of your allow & block settings (including advertiser URLs and categories), so that they may comply and show appropriate ads. These networks compete for your ad inventory, potentially increasing your total AdSense revenue."

But Netmeg, who seems to be doing well, has them blocked. Could you explain to me Google's message above especially this sentense: "These networks compete for your ad inventory, potentially increasing your total AdSense revenue."?

Google's advice isn't always correct across all content types. You really have to test everything repeatedly to see what works best for you.

For broad entertainment categories those networks with CPM targeted ads may work, but in a serious high CPC niche they're probably more of a nuisance.

Experiment for yourself, but give it a reasonable time period (1-4 weeks depending on traffic volume).

I blocked them because I ran them for a while, and then checked the earnings and it was around ten bucks over a period when the AdWords networks made thousands. That's not worth the time it takes to worry about whether or not the ads are good, so I blocked em.