jgbrowning, I'm using your points to extend my argument, so please don't take this as a straight "nuh uh" rebuttal. This is just me comparing and contrasting my opinion with yours.
There's more play in role-playing games than what just occurs between the players and the GM. For those who prefer playing in a pretend world that exists independently of the PCs, there's the game the GM (and the player) plays alone. In this aspect of roleplay the rules function not only as directions on what widgets can do what while at the table, but as guidelines to how to create a "pretend reality" wherein those (player or GM) who prefer to role-play as if the world exists independent of the PCs find help in creating that independent world based upon the rules expectations.
I disagree -- I fundamentally don't believe that the version of the game world that exists only in the GM's head is actually part of the game. It's prep.
Stuff isn't part of the game at the table until it is introduced. After it's introduced, it only matters to the GM whether it was previously extant in his head or improvised, since he's the only one that knows.
I see how there's pleasure to be had in building within the "test server" version of the game world that exists only in the GM's head, and that's a popular activity among GMs, but I don't think it ultimately relates to the actual roleplaying game at the table, the thing that gets played. My experience is that most of the time, the extreme detail in the GM's version of the imagined world is illusory -- stuff in the
shared imagined world, which is the version of the world the game at the table takes place in, is blurred with the fact that it's a consensus among multiple people. Stuff happens, is seen, is felt, smelled, etc., it's a dirtier place than the one in the GM's head. Less Platonic, less ideal simulation.
The reason I keep hammering this point is because I think it's key to the discussion. 3.x is a toolkit that works equally well to play at the table or in the GM's solo version. That it gives GMs guidelines to imagine a rich, developed world is a thing that makes those GMs like it. Heck, it
needed to do that, since GM prep time was fairly intensive. But I literally don't see that as a gameplay issue.
As I said, one type of roleplaying is "The world exists to interact with the PCs" type, and what you've posted is the calling-card of that type. That isn't the only type of roleplaying, however.
Again, I'm arguing here more in a terminology sense than "Nuh uh, you're wrong", but again I disagree. This could be my own personal glitch, or whatever.
My point is that roleplaying (in terms of what 3.x and 4e are trying to do,so that it's not a sprawling "what is roleplaying?" question) is a multiplayer activity. Fundamentally. At least two people involved. As such, there will be a shared imagined space, and that's the "game world". Yeah, I know, it's hard to discuss things that are both shared and imaginary, but if I type "There's a red apple, kind of soft, with a brown spot on the top," I just shared something imagined.
The way I see it, it's important that the shared imagined space feel real, feel supported by mechanics, backstory, etc. in various ways. However, because it's imagined, whether it
seems firmly supported, that is "real", is what matters, rather than whether or not it is actually firmly supported.
That's why I argue vehemently that no, the kind of roleplaying where it's really really important that the GM's solo version of the game world is mechanically supported is not just "another kind of roleplaying", it's roleplaying with an additional GM-only activity bolted on the side. Which is totally cool. I'm saying that the world can be just as real and consistent
in play even if the prep was done in a different fashion.
I totally agree in every way that everyone imagining the shared game world should see it as a solid thing that makes its own sense. That phrase "The world just exists for the players" is too vague there. In one sense, it's literally true in all roleplaying games, the stuff that isn't played, isn't played.. In another sense, it can imply that the world is disposable or somehow less meaningful or important than the players, which I don't think any of us are looking for. The world can come into existence only as needed for the players, and yet be consistent and have a weight and realism all its own. My take is for it do have that heft, everybody at the table, not just the GM, needs to have that buy-in for what the world feels like and how to describe stuff in that context. I think it's much more of a communications skill than a factor of prep, in a lot of cases. That's just my opinon, of course.