[Orrin]

One big advantage text games have is that both development and overhead costs are much lower when compared to graphical titles. You have tools which are more mature, mostly freely available and can be used to produce content far far more quickly and cheaply than with a graphical game.

Because they are cheaper to create and operate you can make commercially viable text games with a much narrower appeal than you ever could with a graphical game. It also means you can produce content much more easily, allowing your game world to change in response to character actions, run frequent special events, etc.

I also think if people are interested in MMOG design then they should seriously consider text games, after all issues of game design, balance, customer service etc. are much the same as in a graphical game, just on a smaller scale.