I think Yahoo's got a problem in SERPs, no offense. I built even more backlinks but still, my site is still down under. Google's algo is different in Yahoo, but it is easier to top Yahoo's SERP compared to Google.
Here is what I noticed guys in regards to google and yahoo. I have a site that hit #4 on google and held its place for over 1 month. During this time, I also was #6 on yahoo. Earlier this week google made a major shift and placed my site on page 6 from a page 1 position. The next day yahoo also lost its position. Now the point I am trying to make is that I truly believe that their algorithm are somewhat similar. One maybe contingent on the other. I am no expert but I have seen this on two seperate ocassions. Thats just my input on these subject matters.
I think Yahoo is after the onpage optimization unlike the google which is offpage optimization. That's only my opinion.. but as you can see google is number one search engine 2nd is yahoo.... so if i where you go for the google...