For Seth Godin’s new book Poke the Box did a neat idea to support the early readers.
For every 5,000 people that signed up to his email list for the Domino Project and gave permission to be contacted he would reduce the Kindle pre-purchase price by $1.00. By launch it had dropped right down to only $1.00.
Toyota is doing something similar in Australia with LikeMyRide, you enter the competition and like the page, for every like the price reduces by $5, the winner can then buy the new Toyota FJ for up to $20,000 off the purchase price. Presumably (like Seth) they can then use the permission of the other thousands of people who signed up to to help them get their own FJ.
Nice framework for you to try, reward your early adopters, incentivise them to share and reward those recipients. Also helps make your product launch a heck of a lot more exciting.