Another look at optimizations

We've given you many optimization tips over the years, and, as you
know, it's important to consider how your ad implementations affect not
only your click-through rate, but your users' and advertisers'
experience as well. To support this, we'd like to remind you of the
following two guidelines when optimizing your site.1. Ads shouldn't be
placed under a title or section heading in a way that implies that the
ads are not ads.For example, ads shouldn't be placed under titles such
as “Dallas Business Opportunities” or “Today's Hot Deals”. Placing ads
directly below titles such as these implies to your users that the
links in the ads are publisher-created content. The example below shows
a placement that does not follow this guideline.2. Ads should be easily
distinguishable from surrounding content.Similarly, you should not
place an ad unit by a group of links that has identical colors and line
spacing. Doing so may cause users to think the ad unit is content
created by you. In this situation, we recommend using a different color
for the ad titles or indenting the ad unit to help distinguish the ads
from your own content. This screenshot shows an implementation that
does not follow this guideline:As you can imagine, users who click on
ads that they think are publisher-created content may lose trust in
your site and decide not to return in the future. It's important to
keep their interests in mind, as well as your own.Also, advertisers can
tell which sites have a high conversion rate for them using Placement
Performance reports. A conversion occurs when a click on an ad leads
directly to user behavior that the advertiser deems valuable, such as a
purchase, sign-up, page view, or lead. Advertisers have the option to
exclude your site from their campaigns and may do so if it is not
leading to conversions.We believe these guidelines invest in the
long-term health of the relationship between AdSense publishers,
AdWords advertisers, and your sites' visitors, and that they will help
ensure your continued success in the AdSense program.

Posted by Meridith Major - AdSense Publisher Support