I agree with [MENTION=58172]Yaarel[/MENTION] that multiple options would have been useful....but there's always next time.
I voted 'text', but I'm thinking something way beyond Zork. What would be really cool would be a text game that can handle multiple independent players (say, up to six; each with one character) in real time, and allow for real-time non-scripted interactions between those characters. So if I've got a Dwarf already in the dungeon and Joe comes in with an Elf and stumbles on to my character he'd get the room description along with "There is a Dwarf here."; meanwhile I would get "An Elf enters the room." at the same real-time moment that Joe gets the room description. We could then interact with each other either by some sort of in-game chat, or trade items, or fight each other, or whatever; or we could link up and move together from room to room. Treasure etc. would be randomized, as would monsters etc.
The chat would only be visible to characters who can "hear" that conversation - thus if my Dwarf and Joe's Elf were chatting in one room Cindy's Human and Bill's Gnome in another room would not see our chat or even know it was happening; but nor would Joe and I know anything about any interactions between Cindy and Bill. Jenna's Hobbit off on her own knows nothing abut any of this. And the 'win condition' is to individually get the most points - some from what you kill, some from the treasure you find, some from finding an exit to the surface - so characters can co-operate for a while but sooner or later will probably separate and-or turn on each other. It wouldn't be a party-based game like D&D in that respect.
If a character died other characters could later find (and loot!) its corpse. The game would end when there are no characters left, or at a predetermined time, or by consensus of the players (there would need to be a meta-chat layered above and outside the game chat for stuff like this, or for people to say they were away from their machine etc.).
The game would also have a 'solo' mode.
My second vote would have been for "none".
Lan-"I'd play something like this till I dropped"-efan