Is "junking" worth it?

We just got over “junk your car” rebates by the federal administration, now it’s “junk the bus.” This program makes sense in terms of the environment, since “junk your car” was directed at saving energy.  It appears to me that junking the bus is more meaningful if you are going for the green. On the other hand, is either program really necessary considering the amount of money involved over a limited time for nebulous result?

Until next time,

Dan