If we simplify the nomenclature (but not the word nomenclature), then the difference between theology and mythology is clear: The former is the basis for religion, and the latter is the basis for some interesting storytelling. In a society where Judeo-Christian theology is the basis for several religions, denominations and sects, it is a tricky thing to present Judeo-Christian mythology without treading on things deemed "holy." As Greco-Roman theology (i.e., outright Zeus worship) is underrepresented in the United States of America, its mythology is fair game to adapt, remix, and mutilate for pop cultural consumption.
Judeo-Christian mythology really doesn't have that option, at the risk of angry fundies conflating their dogma with creative storytelling. It's been done for mainstream audiences, to little controversy: Various retellings of Arthurian Grail legend, the odd-numbered Indiana Jones adventures, and Santa Claus. The devout pitchfork mob assembles against the rest, from The Da Vinci Code to horror movies (the religious backlash for the horror genre is not so much now as it was 10, 20, 30... years ago) to heavy metal music (same with metal, evidently).
I've started to watch a show called Supernatural, which takes Judeo-Christian mythology (heavy on the Christian) to primetime network TV. Prior to the fifth season premiere last week, I've watched only two episodes, and not the whole way through: (1) The one where the elder brother travels back in time to learn that whatever happened, happened, and (2) the one where the younger brother frees Lucifer from hell (the fourth season finale). I skimmed through Wikipedia to fill in the gaps. Since Diablo III won't come out until 2011 (at the earliest, so be on the lookout for "Waiting for 2011" blog titles next year), I think I'll get my dark fantasy fix with this show, albeit in a modern setting. (Swords are more badass than guns, in my opinion.)
Oh yeah, the show gets bonus points for having Jacob from LOST play the role of a human voluntarily possessed by Lucifer (and therefore acting as Lucifer himself).
I am all for creative storytelling that separates the mythology from the theology. Doing this gives the storyteller the freedom to weave some freakin' cool stories. In the universe of Supernatural, demons were human souls transformed in hell, angels aren't that good either, and God is nowhere to be found. At some point, with all this Christian symbolism, the show will have to determine how Jesus fits into the story.
For those who aren't aware of this pop cultural trope, in Western storytelling especially, placing Jesus in an extra-biblical setting is instant, irreverent comedy:
This landmine for comedy is sidestepped whenever Jesus is repackaged as a talking lion that eats White Witches (that intentional double entendre might be a mortal sin), or as an action hero who sacrifices himself for humanity in some sort of metaphorical allegory. It helps drive the point home when the aforementioned action hero has the initials "J.C."
The chances are good that the one "good angel" in Supernatural, an Angel of Thursday Castiel, is really Jesus. (I hope that someone Googling "Castiel is Jesus" or "Jesus is Castiel" will find this blog entry.) Like the dude, playing the dude, disguised as another dude, Castiel could be Jesus disguised as an angel, possessing a willing human being. If you think about it, a zen-like angel who does kung fu knife-fighting on angels and demons is pretty badass. Jesus, a relevant deity of modern society, doing the same thing is pretty silly (see the above embedded videos). However, if the writers go in this direction, and ease the reveal, then it could work...who knows?
In other words, you're all going to hell for reading this rant. (But that's okay, since Castiel will pull you out!)
The show, while separating the mythology from the theology, probably has an overarching sentiment regarding God, angels, and demons. The fifth season has yet to unfold, but the chances are also good that the God in Supernatural is (or will ultimately be) on the side of human beings - not Michael and his angels, and definitely not Lucifer and his demons.
And that makes a good theological sentiment, too.