JenSense

If you log into your AdSense account today and go through the process of adding a new custom channel, you will now see a checkbox underneath the field you enter your channel name into, stating “Targeting: Show this channel to advertisers as an ad placement”. If you check the box, advertisers will be able to select target that channel on your site, rather than having to spend time to pick and choose what pages or directories they want to advertise on.

Of course, this could also have the opposite effect of advertisers deciding to only site target a single channel when they might have site targeted the entire site otherwise.

It is important to note that advertisers will see the name you have provided for the channel. So for this reason, a better descriptive channel would work better (ie. headerleaderboard) than something you have done in your own personal internet lingo (ie. hlb) that might not mean anything to a potential advertiser looking to site target.

Note that this only works for custom channels not URL channels.

To set up new channels for targeting, simply check the targeting box on the setup screen. To make a current custom channel available for advertisers to target, visit the channels listing page, then click the button next to the channel you want to make targetable, then click edit settings. Then check the checkbox for targeting and save the channel info.

As a publisher, you could set up custom channels so advertisers could target the ad unit running above the fold, front and center on your site. Or you could set up custom channels based on the topic of the content for each section of your site. There are a lot of ways publishers could decide to segment their channels to make it attractive to advertisers. When you do it, try thinking like an advertiser and how advertisers might want to run ads on your site through Google.

AdSense hasn’t updated the support files yet with much information on the feature other than this page. There is also a mention of it on the AdSense overview page as one of the tips, but it leads to this page which is the AdSense custom 404 page.

I am not sure how many publishers will be utilizing this feature, or how many advertisers will use it for targeting, although it has been tested before it was launched to all AdSense accounts, which generally means that it was well received by those who beta tested it. It would make sense for publishers to use this who have very large or multi-themed sites where it would only make sense for advertisers to site target specific parts of the site rather than the site as a whole. But it is something new for pubishers to play with
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