Google and Yahoo have there own algorithms for there SE. So, optimize your site keywords for Yahoo also to get traffic.
wow great work!, ive never been to pleased with yahoo traffic, but yet again it all depends on the niche. ive had top listings in yahoo and never received half as much as my #5 listing on google
Yahoo Search engine loves the sites listed in their directory. Google love the sites with high quality back-links. If you can have these 2 you will bring traffic from both of them
atleast your URL is on top for both google and Yahoo... i can understand things are good but not the best...
that mean 99% of your visitor is using google to search instead of yahoo Its seem that everyone using google these day, each day I receive about 10k of uv on google but only 1.5k on yahoo.
anyway ultimately its good from traffic point of view, in one way or other u r keywords are top in top 2 search engine.