First I think Eric does a good job.. no need to try to improve that.

Second in response to Jim..  The Refiners are cranking out lower octane gasoline now because of the economic's.. they are cracking for the highest value which is distillate.. diesel.  The resulting gasoline out of the product stream is lower octane.

They can blend this with butane.. which is carcinogenic or ethanol.  Butane can be used in the winter at a higher mix and is cheaper.. hence the reason that winter gasoline is cheaper but is more volatile and can not be used as much in the summer.. and thus the reason why summer blended gasoline is more expensive.

http://www.energytrendsinsider.com/2013/10/08/why-gasoline-prices-are-falling/

Ethanol is an excellent source of octane and is not as volitale as butane.. (and it doesn't kill you if you drink it.. edit add to clarify: uh-hum denatured ethanol has the nasty stuff in it.. don't drink it!! ) it will work year around.

As far as starving people in Africa goes.. Nightline did a piece a few years ago about US donated corn to Africa.. it was a hit job on GMO as the corn was delievered to Africa but was not used because of concerns for GMO contamination of Africa corn.. that would be unable to be sold to Europe.  So US donated grain sat in a warehouse.. or so the story went.

In many parts of the world.. US grain is too cheap and undercuts domestic farmers which use more labor intensive methods than US farmers.. Consequently Cheap US grain can undercut foreign farmers who can not compete.. and thus the land sits idle.  Africa has wonderful potential to raise crops and grain.. IF THEY SO CHOOSE.. to develop.  I wonder if anyone has looked at increased peasant farmer prosperity allowing for a better diet.. it is possible.  No doubt that price spikes have also had detrimental effects.. but these have somewhat been more aligned with poor weather in major growing area's such as the US.

Over time we should see a new normal that works for everyone.. The US farmer can produce.. ethanol allows us to do what we do best.. produce corn.