The guys behind
Adventurer Conqueror King began a kickstarter for their game. Originally, I simply backed it with a $5 pledge. The more I saw of it, the more I loved it.
Eventually, I upgraded to $40 pre-order. I had input into the design and development and now we're using the game for our main campaign.
We're up to 25 players total and 3 DMs.
This is a game no one heard of until I stumbled upon the Kickstarter for the project. Now, everyone in our group (former 3.x, 4E, AD&D, B/X, etc. players, as well as brand new players) is into the game and many have went ahead and pre-ordered (the game isn't actually out yet).
While I don't think Kickstarter would be the route I'd take if I were WotC or another large publisher, I would certainly look into the model and see if I could do something similar.
Having feedback on a product
before it goes to print, could save a lot of flops from making it to the market.
Also, the tiered system of payment, people paying to playtest your product, etc. - if WotC did something like this for 5E, it would be leaps and bounds ahead of 4E's development and launch.
Imagine, if WotC solicited feedback, had pre-order playtesting, tiered entry into the system with rewards for bigger "backers" (autographed copies, etc.) and integrated all this into their DDI system.
It'd be insane. And amazing.