Our cultural desire for a legitimate epic — a story that feels as if it will go on forever, yet proceeds with strength and intent toward a satisfying conclusion instead of spinning out into endless side-quests and prequels — is mounting. Maybe it's never gone away.
I've written before about my problem with so-called epic storytelling, something Gabriel echoes in his post above: it's too easy for something like that to turn into shapelessness for its own sake, to start as Homer and end up as General Hospital. Hence my general aversion to storytelling as a mechanism to provide people with a bath to lie down in and go to sleep, so to speak. A good story should wake you up, not lull you into complacency.
Another thing I always go back and forth about is what the definition of "epic" is in today's verbally denatured culture, where everyone can be a "genius" and where "disruption" and "innovation" happen six times before breakfast. In such a context, trying to find meaning in a word like "epic" is like trying to squeeze juice from a walnut. The other day, a forthcoming Kristen Stewart movie was announced as an "epic love story", which makes me think more of the battle-hardened likes of Doctor Zhivago than their proposed 1984 pseudo-clone. (Talk about denatured.)
One story I go back to a lot as a pet example of an epic, even though it clocks in at barely 200 pages, is Yasushi Inoue's Tun-huang (reviewed here). It eschews aimless detail for a story that goes many, many places; the details that are there, are all the right ones, and all the ones that prove more interesting with subsequent readings — and it's a hell of a lot easier to re-read something like Tun-huang than today's multi-mega-page cinderblock foot-breakers. The epic-ness of the story isn't in its length, but its scope and its insight. And at the end, when its story is connected back up to the world we inhabit right now, its epic-ness is reinforced all the more.
The problem with our desire for epics is not that we have such a desire, but that it seeks satisfaction in things that are ultimately so quotidian and narrow. Epic fantasy as we currently have it only pretends to take us new places. It shows us some fine scenery, to be sure, but it isn't the scenery that makes for an epic. It's the feeling of having been all those places in the company of another human being worth knowing about.