4) Downloadable content
Why release a book or TV series, when you can just make more game and either give it away or sell it as an expansion? That seems to be the philosophy behind GTA IV
's The Lost and the Damned
and the Fallout 3
expansions. While downloadable content is of variable quality, remember that it is still in its infancy. As it becomes more and more sophisticated in the future I think we can expect to see a lot more interesting things in our DLC, and it is yet another way that a game can expand its own universe.
So there you have it, just four ways that games don't need accompanying books, animated TV series and all that other crap and that's hardly an exhaustive list.
Don't get me wrong, though, I'm not trying to argue against that stuff existing and I'm aware that some of the games I listed above have expanded universe content in addition to the things I mentioned. After all, gamers aren't just gamers - many of us read books, watch TV and indulge in all sorts of other things. It can be nice to see a game universe cross over successfully from one medium to the other.
My point is merely that game developers now have a unique opportunity to build a far more detail-rich world than is possible in other media. That is a gift
and should not be squandered as often as it is by offering an expanded universe as compensation for a lack of in-game attention to detail.