If you go to the store page of some game, you can see in the right column if it uses Steam Cloud or not, below of Metascore and. Por example:

[Orcs must die][1]! has the icon of a cloud and the phrase "Steam Cloud".

[Natural Selection 2][3] not.


  [1]: http://store.steampowered.com/app/102600/
  [3]: http://store.steampowered.com/app/4920/