There is one important point here which bytemaster touched on, but no one else seems to have picked up:

* mastercoin relies on a *centralised* price feed for its CFDs
* bitshares do not

Centralisation is something which bitcoin was designed to avoid at all costs, so this is a bit of a backward step for mastercoin.

The big question for me is whether the proposed technique for bitassets to track the 'actual' price of the asset they reflect will actually work. The white paper is somewhat lacking descriptively.

Cheers, Paul.