The basis for the series this: A critical bullet was fired one day early in 1940, killing the creator of the serum that turned Steve Rogers into Captain America before the transformation could take place. The rest of the series follows the ripples of this event forward.

Hmm, sounds a lot like a DC comics Elseworlds that came out a while back: The Nail (link contains spoilers). The notion is that because of a flat tire, the Kents never find and raise Superman. Actually wasn't that good a story, as I recall. How is Bullet Points?