Very good feedbacks, Mr Guest!

My favorite concept is that of Superku, too. Mainly, because of the magnificent videos of the gameplay.
But, the concept is far from being complete, the graphical concept is completely missing. What is the main character?
You might ignore that in a fps, as long as the player can't see his avatar, but in a sidescrolling pc-game...
When developing this game, I would start with the programmed motions that Superku already got done, build a leveleditor, and build one level after another with only few of the motions of the character needed.
When adding further abilities, those abilities shouldn't touch those early levels, because they could vanish all the effort in building and balancing them.

For the gravity abilities look at "And Yet It Moves" (http://www.andyetitmoves.net/) to avoid too strong similarities. The people shouldn't compare it to that game, it should use the gravity in a different way with a different feeling.