I agree with this post; the buy-back program is costly and ineffective.
A similar program has been in effect in California for some years, as far as I know. This makes sense for specific areas that have a severe pollution problem, like Los Angeles. But nation-wide, it is an ineffective way to spend tax dollars, it will not stimulate any industry and is harmful to the old car hobby.
BTW Maximus' thread seems to have been lifted entirely from this site:
http://www.dailypaul.com/node/77405