I am fairly optimized for Google but not for Yahoo. I gave up for Yahoo. Most of my traffic comes from Google and Yahoo is not that important to me.
I'm with jeros. I'm surprised how many of you value backlinks so highly with Yahoo. I helped a small site with only 2 backlinks rank #1 on Yahoo by just changing the title tag on the home page. Not so with Google!
I think getting backlinks from site having more yahoo backlinks is very important, i did try to optimize a page like that couple of weeks ago and site log is showing traffic from yahoo, infact some of my keywords are now no 1 on yahoo.
I've never tried specifically to target one search engine over another. I just do the best I can with a comprehensive on-page and off-page SEO effort and let the "chips fall where they may", as the old saying goes. The results of that? Of 65-70,000 monthly unique visitors, 53% come from Google and 24% from Yahoo. I'm comfortable with that proportion.
According in my own experience, Yahoo and MSN looks more on site content. So I suggest you to do more Article submission tasks. They will more appreciated those articles.
I've always found that setting your SEO for google brings about positive results in yahoo anyway. That is just from my experience though
I am more concerned about Google. However, Yahoo has indexed my site thoroughly and I am on the third page of results for my designated keyword. I have many linkbacks, so that is definitely a contributing factor.
I've gotten #1 & #2 rankings very easily on Yahoo for very high profile 2-word keywords. While the traffic is nice, it's not astounding...it's probably equivalent to a "bottom of page 2" Google listing for the same keyword. Yahoo seems to like what most people call "over-optimization". Keyword heavy URLs (that is, keywords in the domain name and in the category & page name itself)... keyword saturation (not to be confused with keyword stuffing) at a 5%-10% or so amount... it's debatable if Yahoo still looks at Meta Keywords, too... For many if not most of the competitive words I rank at the top of page 1 on Yahoo for, I don't rank AT ALL for in Google. My guess is that it could be due to over optimization. So, I suppose your strategy could be to over optimize to appear in Yahoo and sacrifice being listed in Google for short-tail terms, or under-optimize and work twice as hard attempting to get ranked for short-tail in Google with unknown results on Yahoo.