I think there's a certain demographic that older versions of D&D (via retroclones mostly) can grow with. It's the same demographic that Oddysey discusses here. I think the "retro-cool" approach is the best way to get it in front of the younger generation today.
The question I've been mulling over is how? How do you take a game that was poplar 30 years ago and repopularize it? How can we make older games of D&D trendy again? After reading this post from James Raggi, he converted me. I believe it can be done. It was just a matter of how. There was something nagging at me in the back of my mind about shoes from the 90's, and it came to me the other day.
Back in my salesguy days working in Manhattan, one of the popular books out was called The Tipping Point: How Little Things Can Make a Big Difference, a book by Malcolm Gladwell. It was all the rage. Click on the Wikipedia link above for a good summary. The book described the conditions and factors under which things became "viral", contagious, or a craze. One story dealt with Hush Puppy shoes. Apparently in the 90's no one wore them. The Hush Puppies company was going to phase the shoe out. They were basically sold only in mom and pop stores in places like East Bumfuck, Alabama.
Anyhow, some people in NY City in the Village started wearing them, as a fashion statement, a retro-cool thing. And it caught on. Like wildfire. Next thing you know, major fashion labels are using them in high end fashion shows, and millions of shoes are sold all around the world.
All this came from a few people wearing them in a small (but trendy/influential) section of NY City.
The book is filled with stories like this, and details the kind of people and factors that go into making something go from something a few people do, or are a fan of, to a contagious epidemic of cool that everyone has to have.
A lot of us remember the Grunge days well. Who wore flannel on a regular basis before 1991? People in the woods of Washington state where it was cold did. The clothing people in upstate Washington wore on stage, because its was only clothing they owned, became de-facto Grunge-wear. Again, high fashion eventually co-opted flannel for the runways (which was pretty much when I knew the scene was over, but thats another story).
I think the same thing is possible with older editions of D&D. I think the OSR could finally burst out of its shell of a half dozen boards and a few hundred blogs, and really become something mainstream. Right now it seems to exist more as a reaction to new gaming trends, or act as sort of a "coming back home to where it all began" event for many older players.
As far as getting new players to older games and their clones, the way the clones are written is fine if you're going to target it to a market that gets the new school game and is wondering what old school is all about. But to a demographic that doesn't know anything about the game at all, other than that geeks played it 20 years ago, the intro/description/flavor/character/style/feel/vibe that a reader has to "get" in order to describe it to his/her friends while they're hitting the bong needs to be whimsical/fun/funny/over-the-top/ironic/retro-hip. The current mood or vibe of the clones won't attract people who never played it before, since there is no point of relation.
I think the audience for it are the same types of people who Oddysey describes who collect vintage records, or who hit used clothing stores for the vintage look. It would be the latest "cool find" to share with friends.
I has to be a game that would be explainable to newbs in the time it took to have a drink, or pass around a joint. Simple and basic. Two minutes tops. Players shouldn't even need to reference the books during the game.
It would essentially be Swords and Wizardry repackaged to have some sort of retro-cool character/feel to it. Right now S&W is written to be a game that is bare-bones rules, but is lacking in character. Any character it has and any flavor it exhibits are language meant to distinguish it from new school games, and describe its rules-light approach, and the principles in Matt Finch's Old School Primer.
The number one requirement though is that it has to be a simple game.
And preferably in a format that can be played with everyone sitting on a couch, with maybe a coffee table in the middle of everyone for rolling dice.
It can't take itself too seriously. The whimsical approach to dungeon design exhibited in the early days would be the way to go to attract this audience. One minute you're running from a platoon of orcs, you jump down a hole, and the next you're in "Alice in Wonderland".
(I had hopes for Hackmaster Basic hitting this demographic, if they could keep some of the old whimsy, but they blew it with the level of detail in the game.)
After a new guy plays it for the first time with a group of friends, he can go pick up a copy of it at a bookstore, throw onto the shelf next to Pictionary and Scrabble, and then HE can be the cool guy who "found" this old/new cool game and introduced it to HIS other circle of friends. Of course he would have to tell his friends that when HE found the game, he didn't buy it at Barnes and Noble, but had to get it from some hard to get/exotic place, to keep the aura of mystique and exclusivity surrounding the game. He may let slip that it might be found on Amazon now though...
Eventually it will end up in the hands of people who are described in The Tipping Point as the types of people who get things to spread like wildfire.
Like I said though, I think in order for this to happen, in order for the game to be attractive to folks like this, something about the clones needs to change. The vibe is wrong to attract newer people who have never played the game before, and who have no experience with RPG's.
Next, good DM's need to play the game with people they don't normally play with. Try to expand the exposure of the game to others who don't know what D&D is. And for God's sake tell them where they can get the game afterwards.
The more people do this, the more exposure the game gets outside of typical gamer circles, the better chance the game has to go viral again.