It is clear that Google has a strong Love / Hate relationship with Affiliates, which typically boils down to whether you are using their services and how large a volume you are generating in sales.
Here is a really interesting Infographic that Aaron Wall put out, which details some of the love, and of course some of the hate, Google has shown affiliate marketers over the years.
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I have just been searching for this type of information for a while and finally found here so far. Thanks !