I have noticed lately that 80% of my traffic is coming from Yahoo searches. It appears that i am no.1 in the UK for the search 'free xbox 360', and about 3rd for 'free xbox'. However on Google i am no where to be seen! Is there a reason why i am ranked high on Yahoo but not google? Site: 360Claim.com
What type of things have you done in terms of SEO? I ask because often times Yahoo! tend to put more weight on on-page optimization such as title tags, page content, etc. and Google tends to put more weight on off-page optimization such as backlinks, external anchor text, etc. You may want to equally execute a strategy which includes both on-page optimization and off-page optimization. I also noticed your site is a single-page site. It is much harder to rank a single page website. I would suggest you focus on some content building and build out some content pages for your site, this may help increase your site ranking in Google.
Each search engine has its own algorithm - and ranking well on one does not mean you will rank at all on another. Google places much more weight on the quality and relevancy of backlinks, and domain age. Yahoo's algorithm is about 2 years behind google. What no longer works with google, will often still work with yahoo.
Yahoo puts a lot of weight on your domain name as well. If you have the keyword or part of the keyword in your domain it is actually quite easy to rank for that keyword, assuming its not too competitive. Many of my blogs rank for there keyword in yahoo because of their domain; these blogs rank fairly poorly in google, however. In your case, you have 360 in your domain name. Also, like others here have stated they value on-page optimization a lot in there algorithm. Google is the #1 search engine because they have become an expert in showing some of the best results for a search. They do this by somewhat successfully preventing spammers and spam sites by placing more emphasis on off-page optimization in there algorithm (which is harder for people to manipulate). Therefor, unless you get a lot of backlinks from relevant websites for your keyword, it is pretty difficult to rank high on Google for anything with more than 500 searches per month.