Microsoft announced how Cortana, Microsoft Bing's personal voice search assistant, will only work with Microsoft Edge in Windows 10. Microsoft wrote:
Starting today, to ensure we can deliver the integrated search experience designed for Windows 10, Microsoft Edge will be the only browser that will launch when you search from the Cortana box.
Danny Sullivan wrote a big story on it named Microsoft blocks Google Chrome & other browsers from Cortana in latest Windows 10 release.
Microsoft did add, "of course, you can continue to use your search engine and browser of choice on Windows 10." They then explained how to access it by saying "they can be accessed and used as you always have. You can easily use our centralized default manager to choose your preferred default program for everything from browsing to email, and you can configure the search default setting in Microsoft Edge and Internet Explorer, which are available when you directly access those programs."
Of course, Microsoft wants to control as much of the market share they can within their own software as possible. But is it fair? Google does have the vast majority of the market share.
One searcher told me it does often make him spend more time on Bing, despite preferring to use Google:
@rustybrick @seroundtable Gotta say, I find myself using Bing sometimes because of this & I normally always use Google. This is big.
— Douglas Sewell (@DouglasASewell) May 2, 2016
Forum discussion at WebmasterWorld.