Dueling is a fun thing that most PvPers would enjoy. Please don’t just implement it without adding some extra little functions. I’d personally like to see clear duel stats, maybe a title upon duel-win streaks or something, and perhaps a small window which provides us with a duel ladder-type of system.
A duel will not be the measurement of your skill. However, it will measure your knowledge of the game, creative use of skill mechanics, and your general strategy/intelligence/cunning in a fight.
The ability for groups of players (max 2 IMO) to duel another group would be pretty interesting also.
In short, dueling alone would be greatly appreciated, but with these added features it would make dueling more interesting.
<witty and somewhat pretentious attempt to appear intelligent>