The Xbox One March update is being pushed out as we speak, and it introduces a number of new changes and features which make the experience of Xbox One better. One of these new features is the ability to search the web with voice commands. Now, when you say Xbox Bing, you'll get results from not only the Xbox Marketplace, but the entirety of the web too.
The official blog post says: "Today, as part of the Xbox One system update, we are expanding search to include web results. Now any time you search with “Xbox Bing,” you will receive results from our expansive marketplace as well as relevant items from the web. And when using Internet Explorer, you can now highlight text on the web page then press the menu button to engage Bing search." The Xbox One March update is rolling out now. Other changes in the update include improvements to voice and party chat as well as UI tweaks and more.