The lengthy mission statement from its website states:

The lack of game-specific research has prevented many in the academic community from embracing game development as a serious field of study. The Journal of Game Development (JOGD), however, provides a much-needed, peer-reviewed, medium of communication and the raison d'etre for serious academic research focused solely on game-related issues. The JOGD provides the vehicle for disseminating research and findings indigenous to the game development industry. It is an outlet for peer-reviewed research that will help validate the work and garner acceptance for the study of game development by the academic community. JOGD will serve both the game development industry and academic community by presenting leading-edge, original research, and theoretical underpinnings that detail the most recent findings in related academic disciplines, hardware, software, and technology that will directly affect the way games are conceived, developed, produced, and delivered.

The Journal of Game Development was established in 2003. It's hard to find any information about the issues but at four issues per year, I estimate the last issue was distributed sometime in 2005 or 2006. It had a good editorial board of college professors and a founding editor from Ubisoft. The list of articles looks good. The price was reasonable.

So what happened to it? Its website recently went down but you can see the last Archive.org version.

The editor-in-chief is a professor at my school so I intend to ask him in person in a week or two, but I thought I'd see what you might be able to dig up about it first. Of course I will be sure to add an answer with his official word on the matter at that time.