Apology: I officially apologize to everybody for being partly responsible that computer game studies are now so often described as a simple conflict between ludology and narratology. What can I say? I'm sorry, it just seemed like a good idea at the time.
Well, I for one don't think you have anything to feel sorry about. Ludology should indeed be a central part of computer game studies. There might of course be other approaches, however, these should take ludology into account in some degree. Computer games might be narrative in one form or another, but they are always about game and play. Of course narratives and games are not excluding one another. On the other hand there has been a narrative turn during the last decade turning everything into narratives and we had to say: Games are not necessarily narratives. Sometimes the narrative even conflict with the game itself. We have seen lots of games trying to be narratives, while the best part of the game is, that there are indeed games.
Remember, poetry isn't necessarily narrative too. Nonetheless, we accept poetry as an art form in itself.
Narratives are one kind of expression, games are another. Game and narrative may be mixed like poetry and narrative may be mixed. Still, games are all about reaching the goal, while narratives are all about reading for the plot.