Games: why it's important to write about their structure, content and style, genres and characteristics, their use and their utilisation of technology.
Dangerous question, and one with as many answers as there are people doing research in the field (and some for the people who are not).
This is the question I have been asking myself for the last ... seven years? I think I have been asking it longer.
In 1991 I started playing computer games not just to enjoy them, but to learn about them, trying to figure out what made them almost addictive. Anything with that kind of holding power had to be a good medium for communication and spreading information, particularly a good teaching-tool and an agent of attitude change. From 1994-1996 (published in 1997) I worked on understanding a game created by the Norwegian board of Health to teach boys about sex and gender. The game, called Det store manndomsspranget (the great step to manhood) was never published, even after almost 6 years of developing it - the christian Prime Minister stopped it in 1998, saying it might lead to lowering the sexual debut age in Norway. If you ask me... that game was so boring, it wouldn't have made anybody more interested in sex. It made a good object for study though, and with its many flaws and complex structure it made me ask again about whether games could be used for the purpose of changing attitudes at all.
By now I think: no, it is not a good agent of attitude change. It's a good way to learn things that should be remembered, and new knowledge can lead to changing attitudes - but the game itself is considered a game, something apart, something not to be integrated in the set of experiences which act formative. Games are by nature outside of real life, and distinguishing the difference is a sign of sanity.
Why are they still important objects of research?
Their structure can teach us new things about perception, about the potential of a new media for widening our knowledge of how humans receive and act on impressions, stimuli, how we focus and about the human ability to multitask on several levels.
Content teaches us what can be talked about in which manners. Where are the taboos and do they change when they are discussed in the medium of a game, with the potential for choosing and discarding which a computer offers?
Style teaches us how aesthetics connects to function, to the social and to economy, as well as about identity and the formation of identity based on the complex messages of style - and yes, you should read Subculture, the meaning of style to know what I am aiming at.
Genres - that's more a matter of understanding the interplay between economy, literature and old styles of games - how history influences the development of what is considered new.
Technology is pretty obvious at least to me... but again economy, culture and the diffusion of innovations - and no, I am not just talking Rogers here.
Espen has his own answers to this question. I have a little problem with his view of games as an object of study in themselves. While I find them important, I want to understand how they connect to the wider media world. They are not isolated, no more than literature is isolated from other media, or perhaps a more obvious example, as literature strives to be isolated: Television from film, radio, music or popular written literature or journalism... we are facing a world of composite media, and computer games are becoming an important part of that.