Apparently the Xbox One streaming will only work with Xbox One exclusive titles.

The Xbox application in Windows 10 allows for connection to your activity feed and voice/text chat. Using the streaming it is possible to stream games from your Xbox One to a PC or Tablet device running Windows 10 and play with friends who are playing on Xbox One. During the demo phase we saw Fable Legends being streamed to the PC and being played on the PC while the other user was on an Xbox One. We also saw a demo of Forza Horizon 2 being streamed and played from a Windows 10 tablet.

While it has been talked about a lot, there was no mention of streaming from the Xbox 360 or the streaming of Xbox 360 titles. Sources tell us that 360 streaming of some sort still might be possible, but at least for the time being it is not something Microsoft is talking about. Still we would not rule out the possibility. Microsoft promised more Xbox One and PC gaming news coming at GDC in March as well as throughout the rest of the year.