This should be limited to the first post of a thread a user creates.
No other adsense code should be displayed in threads this is enabled for.
Possibly enabling threads for adsense by checking the user has it enabled and their code saved somewhere, as he/she creates the topic.

See this type of forum at www.cellphoneforums.com

Is this possible for YAF to implement?
Or do I need to do this on my own somehow?

Look I could care less about the forum in question.
It is their use of adsense in it, which I am interested in.

The suggestion and question is not invalid.

I will endeavor to find a better example so that I may be taken seriously if that is what you require.

http://forums.digitalpoint.com

I gues a beter word for it is revenue sharing from digital's FAQ:

http://forums.digitalpoi..._faq#faq_revenue_sharing