I'd personally say Google just because it is much more popular, but I have no real backup to show you that's it better.
well i think yahoo as whenever a site gets listed in search engine yahoo and msn are the first one to register...
SEO is a general term and have common set of rules that every major SE obeys. Still its hard to appear in high SERPs in Google.
easier?i think the answer is yahoo. but if you ask which one is the most potential, i will answer Google
Yahoo is easy one!!! Google serp keep changing always, depending upon the back links to your site. Google Search Engine accepts quality backlink only .. be patient.
Yahoo is much easier in my opinion. Google is harder to keep up with, although it's reasonable, Google is just trying to protect its reputation and advertisers.
ofcourse yahoo, msn have much easy algorithm so poeple attract towards their search engine result but people cant get benefit from yahoo, msn so although google is tough but give u rewards once rank.
Yahoo is easier. But you can't get more traffic from yahoo. I get more than 80% Traffic from google.If you are doing seo then you have to target google.
If you understand the guidelines of the both search engines, then it will be easy to optimize for both google and yahoo. as per my analysis, google is the tougher one than yahoo. but you can get good amount of traffic with google. so i would definitely prefer google.
Personally, I believe SEO is already tough. I don't see many SEO that really optimize sites for Yahoo search engine, as they all are concentrating more on google. I suggest you to do the same as you may waste your time going in wrong direction there.
Given everything equal, I find that Yahoo tends to give my new sites higher ranking initially. Having say that, 80% of my traffic still comes from google.
SEO is not an easy process, but while comparing with those can say Google is more common and getting fast result