Yes, the Xbox One can play CDs and will support DLNA streaming
Sony announced some details on things the Playstation 4 can and can't do, and I had sent a question over to Microsoft about whether the Xbox One would be able to beat those features. I've just now received an answer and, yes, the Xbox One can play audio CDs.
The system is also DLNA compatible, and they're in the process of being certified. As for mp3 playback… well, that's kind of a mixed bag. The system is a Play To receiver, so you'll be able to stream your content to the Xbox One using any Play To supported devices such as a Windows 7, 8, or 8.1 enabled PC, Windows Phone, etc.
