There is a lot of valuable work that can be done for a few tens of millions to hundreds of million per year. The biggest value is in actually making a commitment.

I think the prize aspect is theoretically valuable to prevent buerocratic waste. However, is there really any evidence this would really work? The x-prize has far more modest goals and has not met its original time window and there are no obvious expected successes. For a Mars prize to work it would have to come close to the expected cost unlike the x-prize and possibly more due to the risk of spending a lot of money for nothing if you get beat. From a business stanpoint it doesn't sound like all that great an idea to me. I guess my stance would be lets try it then drop it if there are no serious contenders within say 3 years.

Regards,
Mark