As always, this kind of stuff is filled with "maybes," "probablys" and "perhaps one day" — that's the way rumors go. But it's also tantalizing enough that one can't really ignore it, though as always, take this info with a big grain of salt.
Anyway, over at Badass Digest, they're reporting that David S. Goyer has pitched a "Sandman" movie, based on Neil Gaiman's celebrated comic, to the guys in suits at Warner Bros., and they have been "receptive." Of course, that could mean a lot of things, but we'd wager that since Goyer is well regarded at the studio (thanks to "The Dark Knight" trilogy, "Man Of Steel" and the forthcoming "Batman Vs. Superman," as well as the brewing "The Flash") that they took the time not afforded some random person knocking at their door to hear him out.
So what makes this rumor have a bit more meat on the bone? Well, DC dude Geoff Johns apparently likes the concept, and Joseph Gordon-Levitt is reportedly "involved," but how deeply at what is described as "the most vestigial of stages" is unclear. Perhaps Goyer simply asked JGL if he's want to read the script when he was done, and if he'd be interested to play Morpheus (which he's apparently "intending" to do)? We could buy that. Anything further, we'd be a bit surprised. But most crucially of all, whether or not Neil Gaiman has been contacted about this isn't certain yet.
As fans know, "Sandman" is famously one of those "development hell" projects, with a version in the '90s kicking around with Roger Avary to direct from a (widely reviled) script tinkered with by a handful of writers. Then around 2010, it was mooted as an HBO project with James Mangold attached that never went anywhere. (Read more about those versions right here).
Frankly, we don't see WB putting too much heat on this just yet, as their eyes are likely firmly on "Man Of Steel" and world-building until the eventual "Justice League." Is it on a desk somewhere as a future possibility? Sure, why not, but the development process can be long and cruel (as previous iterations prove) so we'll see what eventually happens.