Incredibly fun. The story is so gripping and exciting. The music in the game is fantastic. The graphic is awesome.
Although it's a new change in RTS games, Massive Entertainment did quite a good job. Using lots of cinematic moments and ingame moments to tell the plot. And with its graphical superiority and amazing voice casting, it tells the story the right way.
World in Conflict is not only a change in RTS, it's also a stepping stone. After you played this you will want all the other RTS to come or surpass this level of quality.