I think linearity is just fine, when done properly, as not every game should have an open-world. Granted, RPGs are a good genre for open-worlds, given the whole "explore places and customize your character" notion, but they do not necessarily need them. Linearity allows one to guide the player along a carefully crafted experience in a way that open-world games do not. For instance, imagine if, instead of just dropping you into a giant, generic meadow, Oblivion sent the player on several quests inside a few really awesome levels in order to tell its story, but kept its leveling system? It wouldn't necessarily be a better game, but it might be just as good. It would probably even appeal to fans of, say, platformers, who want to get right into the action instead of running around Not-Middle-Earthia for five minutes first, thus opening up the genre to a whole new audience. The linear RPG is certainly interesting concept, and a subgenre I feel needs more attention paid to it. I've seen it done well before, in The World Ends With You (which, though taking place in an open-world, often has the non-essential sections of it blocked off during most of the game), and I'm hungry for more.
