Possible confirmation of a Photo Stream service in iOS 5 has come after users spotted hidden references to the service inside the current version, iOS 4.3.



From TUAW:

The expectation is that Photo Stream will work for your photos in Photos.app the same way Playlists work for music in iTunes, allowing you to send albums of photos to friends. Its background appearance in iOS 4.3 may indicate that it was pulled at the last moment and will instead be part of the major iOS 5 upgrade rumored to be out this fall.

  Photo Stream feature hints found in iOS 4.3