It really doesn't matter even if the Yahoo and Bing have become one. Google will always stand 1st in search engines race. The ratio will always be remain Google / YahooBing : 80 / 20 as the algorithms of Google has always been good and regularly updated to improve the search results. Whereas, if you look at Yahoo and Bing, you will find a lot of unwanted sites coming up in the search results which are not much relevant to the search terms.
I think Google is better then Bing and Yahoo and we can get more traffic from Google then other search engines.
I didn't check it but I'd say in Europe the Yahoo-index is a bit lower than you said, maybe it is 80/15/5.