Straight from the horse’s mouth:

We’ve started testing organic (also referred to as algorithmic) and paid search listings from Microsoft for up to 25 percent of Yahoo! Search traffic in the U.S. The primary change for these tests is that the listings are coming from Microsoft. However, the overall page should look the same as the Yahoo! Search you’re used to – with rich content and unique tools and features from Yahoo!. If you happen to fall into our tests, you might also notice some differences in how we’re displaying select search results due to a variety of product configurations we are testing.

If you haven’t given Bing much attention now would be a great time to review your Bing SEO strategy.

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