If the greatest of an upcoming movie saga is based on the awesomeness of its fan art, then Stars Wars VII would be the clear winner. If judged solely on the coolness of its logo than Batman V Superman: Dawn of Justice is the champ. If so much of the BVS art weren't parody based, than it would be a technical tie based on volume alone.
The latest addition to the BVS awesome logo field are these two little creations from digital artist Hobo95 (who made a splash a few days back with his nicely done Star Wars VII posters- which are attached). The Superman logo made of either bats or butterflies (a soul symbol)-it is hard to tell- not only symbolically portrays the title struggle but perhaps foreshadows the death of superman in the Zack Snyder directed opus. The second neatly creates a Superman shield out of Wonder Woman's lasso of truth.
Either one will generate a lot of speculation and debate.
Here are his Star Wars VII posters.