The topic of finding a replacement for piston engine fuel came up recently in a CAP Talk post. This month's AOPA magazine has done a five page article on the progress towards a replacement. It is good reading and I am assuming that most CAP pilots are (Or should be) AOPA members. The article might be online but I have not checked.
BTW, immediately following the avgas artice is another great eight page article on the B-25 Mitchell. Great photos in the air of this beautifully restored aircraft.