Rogue has nothing to do with the night blade class, thieves' guild etc.
Rogue-like games are games that are generated randomly every time you play them. The game is never quite the same twice. These kinds of games usually consist of premade "rooms" with exits and the computer randomly selects which rooms to use and where to place them. I'm not sure if this is even possible on something on an MMO scale... but... wouldn't it be kind of cool?
For those of you who have no idea what it would be like imagine this:
You enter the dungeon and each time you enter it you have no idea where the bosses are or what bosses you will even be fighting-- it changes every time you go into the dungeon. There would be normal rooms with normal enemies (duh) and boss rooms where the game would randomly select one of a small table of bosses specific to each room. So you know your first boss will be boss A B C D E or F, but you never know which one until you get there. Likewise, perhaps the second boss could be B, D, G, H or I (but B or D would be eliminated from this table if they spawned in room 1). The final boss could, and perhaps even should, be the same all the time, but the journey to the boss and the "sub-bosses", if you will, would not.
It'd be kind of a nice change from having to grind the same tired old dungeons every time to get your currencies/ph4tl3wt. I don't think we will have such currencies in ESO (at least I hope not) but there's still a high probability that we will be farming dungeons for loot so... why not spice a few up (I'm certainly not suggesting all of them) to make things dynamic and interesting? Just a thought... though I doubt it'd be possible on this scale.