Bing, and other software companies, like Google, tend to roll out new features slowly. So they might roll out a new feature first to 1% of users, then 10%, then 50% and then eventually 100% of users.
A WebmasterWorld thread points out that while Google is experimenting with showing only seven results, Bing is often showing well over ten results for a search query. For example, I searched Bing for ...
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