Have to agree that for me, Yahoo traffic doesn't convert - and there's not a lot of it anyway. So optimise for Google and ignore the rest.. they will follow to a certain extent.
I believe yahoo uses google search, so if you are indexed by google you will be indexed by yahoo shortley, patience is a virtue
hmmmn... take note that Google is a lot faster than yahoo. That could be a reason. What's more, if you didn't use robots.txt, chances are google spidrers would have had crawled your site more often than yahoo. Google by defaults crawls your site every week... yahoo doesn't do that. another thing to consider is that google indexes jpg, gifs, docs, pdfs more than yahoo does.
I've been with google for as long as i can remember, however yahoo image are lacking and im switchin to google! plus google maps beat yahoo maps any day of the week.I like google morethan yahoo.