goodroi - 5:46 am on Jan 6, 2005 (gmt 0)

Yahoo has indexed your site. They are just not ranking it very high (which is also why you are not getting alot of traffic).

Google has not indexed 41,000 pages from your site. If you search on Google you will see that they show just the url, and not the title and description. This means that Google knows the page exists but hasn't been able to crawl and index it.

Adsense is not impacting you and yes it is always possible to be on Yahoo's penalty list. I would suggest just getting more links, review your site for any possible dupe content and look into mod rewrite so the engines can index the rest of your site.