what is the morality of a carrot?
A carrot is a physical object and also an idea. neither deal with morality, until some outside force uses them.
Imagine taking away someones food supply, there are some deep moral questions there.
BitCoins are bits of data and an idea, but the idea of bitcoins have the ability to change the face of the largest industry on earth, the financial industry. If every web surfer in the world started using bitcoins instead of the dollar (or any other currency) I believe that the establishment would resist this change and i am sure there are some moral issues involved in that.
Maybe I should have said: what is the morality of humans using bitcoins?