Google finally decided to pull the plug on the Adsense referral program and has started sending out emails to Adsense users. We at nosum.net, have decided to stop using this product a long time ago! They weren't very effective and would often publish the same ad continuously for a number of page views. They do not give any specific reason but it is safe to assume that the ineffectivness and difficulty in generating revenue for the user, are definitely the causes. Referrals is one of the five products that Google Adsense offers, others include Adsense for Content, Adsense for Search,Video units and Adsense for Mobile content.

 Here's the email from Google: 

______________________________________________________________

Hello,

Thank you for participating in the AdSense Referrals program.
We’re writing to let you know that we will be retiring the AdSense
Referrals program during the last week of August. We appreciate
your patience during this transition and here are some alternative
options to consider:

   * Google Affiliate Network: As part of the integration of
DoubleClick, the DoubleClick Performics Affiliate Network will now
operate as the Google Affiliate Network for advertisers targeting
users located in the United States. Similar to the AdSense
Referrals program, the Google Affiliate Network enables publishers
to apply for advertiser programs and get paid based on
advertiser-defined actions instead of clicks or impressions. For
further details, please visit:
www.google.com/ads/affiliatenetwork.
   * AdSense for content ads: If you have less than three AdSense
for content ad units on a page, you may wish to replace the
referral ad units with standard AFC ad units.


If you currently use referral ads, either to promote Google
products or offerings from AdWords advertisers, AdSense Referrals
code will no longer display ads beginning the last week of August.
We encourage you to take the following steps before the product is
retired:

   * Remove the referral code from your site(s): Please take a
moment to remove all referral code from your sites before the last
week of August, so you can continue to effectively monetize your
ad space.
   * Run and save all referrals reports on your desktop: Create
and save all reports related to the referrals program on your
desktop, so you continue to have access to your valuable campaign
information


Why is this happening?
We're constantly looking for ways to improve AdSense by developing
and supporting features which drive the best monetization results
for our publishers. Sometimes, this requires retiring existing
features so we can focus our efforts on the ones that will be most
effective in the long term.  For this reason, we will be retiring
the AdSense Referrals program. If you have any additional
questions, please visit our Help Center:
http://www.google.com/adsense/support/bin/topic.py?topic=14882

Sincerely.

The Google AdSense Team

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