Hi

Nowhere is Google lucid enough to say "you should use nofollow on affiliate links". The only guidance they offer on this is:

"Links purchased for advertising should be designated as such. This can be done in several ways, such as:

•Adding a rel="nofollow" attribute to the <a> tag..."

Affiliate links are not 'purchased' and Google is not likely ignorant of the big affiliate programs out there. In my case I did say "if you are affiliated with a 'trustable' source there is no reason to try to hide anything from Google". In my case the affiliate links were to a very trustable source that I am no doubt Google is very much aware of as an affiliate provider. And I see no reason to nofollow them (other than paranoia generated from so-called SEOs) if removing this attribute improves the website position in search. Obviously it does depend who you're linking out to and perhaps how frequently

Thank you very much for your reply. i do appreciate it as i am a novice and coming on a forum like this can be quite intimidating. also can i ask you this? the amazon link is an iframe (dont really know what that is) but from looking around it seems that they cannot be crawled from bots anyway. So would could you shine any light on that for me ? thanks a lot

Generally affiliate links do not harm SEO unless they are coming from a harmful network... The biggest reason many sites get slapped with a penalty is because they try and hide (Cloak) the links from either the search engines or its visitors with one method or many.. Which of course is against their policy.
Google can't punish genuine affiliate networks as they would soon find themselves with endless court cases with Google pushing affiliates out of market place and arguable would be because it would seem they would rather see everyone monetizing out of Adsense rather than using other monetization methods.

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