Xbox's cloud gaming systems are a bit limited right now, as you can only play a selection of titles via the technology, and in a limited number of ways. But, as the cloud clearly has a place in the future, Xbox is currently lining up a big improvement for the technology this year.
As noted in a message exchange between NASburg and Phil Spencer, the Microsoft Gaming boss has stated that we can expect to be able to play owned Xbox games via the cloud sometime this year.
When asked about when we can use owned games on xCloud, Spencer simply added, "should be this year".
It should be said that there may be some limits to what owned games are available via xCloud, as the streaming rights for Activision Blizzard games, for example, are owned by Ubisoft due to the agreement that was made in order to get the massive publisher acquisition approved, a decision that will no doubt also impact and limit how Activision Blizzard games are made available on cloud for Game Pass subscribers for the time being.
Thanks, Windows Central.