What are on-site on-page guidelines that can optimize a site for Yahoo search?
Its been over 6 years since I have been running a number of websites and for some reason the traffic and ranking from Yahoo has always been disproportionally low. Given that Google sends so much traffic (except for one site which dropped last week - the topic of another question), I never found out what Yahoo likes (and other engines but lets leave this question Yahoo specific).
Lets exclude things like 'great content', 'good navigation', 'user-oriented text' etc which are a given basic for any site and search engine. I am already passed this ;) What I am looking for could have to do with page structure, linking structure, layout, length of various parts, etc.
Just a note, my sites are all indexed crawled by Yahoo already. Their SiteExplorer shows that they have index most pages (from 10s to 1000s for bigger-sites), just that they rank less well outside of Google.