A few weeks ago, I wrote about my experience with Google’s new Ad Review Center. This tool enables you to block advertisements from certain advertisers. When you use this feature, advertisers who want to bid on your ad space must be approved first.

But it’s not quite that easy. There are a lot of advertisers who aren’t going through the bidding process, so they can still end up on your site without your approval. To block them, you need to use the competitive ad filter.

Initially, this whole process was appealing to me, because I had advertisements for a lot of scam “business opportunities” showing up on my sites. This process helped me eliminate many of them. It’s not a foolproof process, and there are still plenty of scams that can easily pop up pon my sites.

Early on, I noticed advertising revenue had increased for my sites, as users were clicking more often. Google warns that revenue could easily go down if you’re eliminating advertisers from the bidding process. (Fewer bidders often leads to lower bids.) But I found that even though per-click revenue was going down, overall revenue was going up for my sites because I was getting more clicks. I theorized that my readers weren’t interested in the scams anyway, so were not clicking on them. Cheaper, but more relevant ads were driving revenue up.

I wondered if it would last. It has. I have seen per click revenue drop as I continue to exclude advertisers from my sites. But the number of clicks by users has continued to be well above the number of clicks I used to get. So overall my results are positive. But don’t get too excited… revenue is up only about 2%. But I’m happy that the scams are getting less air time and I’m still doing a little better in terms of revenue.

I’ll keep you updated….