I see that you folks are hijacking the RPG argument to discuss RPGs instead. I understand why you would like to talk about RPG instead of RPG. So, I will graciously pass the salt and join in the fray to give my 2 cents about the SP RPG vs. the MP RPG.

When you play a role playing game online there is an option in many games to go it solo. In effect you are playing SP in an MP. I do that a lot, but not always, in Sacred depending on a variety of factors. So an MP game has the potential to give you the best of both the SP and the MP experience.

As to which is intrinsically superior, it depends not only upon the attitude of the gamers, but upon how the games are developed as well. For instance, the majority of folks agree that the SP campaign in NWN is vastly inferior to the MP modules. In other games the MP and SP games are identical.

Those of you who played Goldeneye on the SuperNintendo system might share my opinion that the MP game and the SP game were both a heck of a lot of fun. And while Goldeneye was not an RPG, it did have RPGs in it.

The question is not, Can they reason? nor, Can they talk? but, Can they suffer?
~Jeremy Bentham