Quite recently, we told you that Yahoo was going to start testing with Microsoft soon, and today, they have officially announced that Yahoo is now testing organic and paid search listings from Microsoft’s Bing powered search backend.

Yahoo has begun testing displaying organic and paid listings using Microsoft’s search engine Bing. The only difference between the older and newer search is that the results will no longer be served by Yahoo, however, the interface and design of Yahoo search will remain the same.

As seen in the screenshot above, the organic search results in the yellow boxes are powered by Microsoft and include a mix of both organic and paid listings, the rest of the content on the page is still processed by Yahoo themselves. Right now, the Microsoft powered search listings will only be displayed on Yahoo web search.

However, Yahoo is also planning to include the Microsoft powered search listings on Yahoo! Mobile properties. Yahoo plans to roll out full Microsoft integration to all US and Canada users by August/September timeframe. More at the Yahoo! Search Blog.