This is all bordering in ridiculous in that none of these coins have been shown to have a real implementation in the wild.   People are betting on untested prototypes! 

Mastercoin - doubtful how this approach of protocol layering prevents double spending.
NXT - Closed source implementation.  Does anyone have any idea of how this actually works?  How fair is the distribution when all coins were bought for a mere 21 BTC.
Colored Coins - Fortunately, they don't have a ridiculous buy in vehicle to support their work.
Bitshares -  So these folks use a bitcoin like clone to raise funds.  They are redoing everything from scratch.  Anybody's guess that this even works out.
eMunie -  I heard about it 6 months ago, not certain if their multiple simultaneous block chain forks really work.


Anyway, my plan for iXcoin (The Internet eXchange Coin) is dirt simple.

Stick with tried and proven Satoshi Nakamoto bitcoin technology and layer on top of it Colored Coins.

iXcoin surprisingly has already secured 1/2 of all bitcoin network hash rate.  So any financial instrument you layer on top of iXcoin will automatically get the tried and proven security of 1/2 of the bitcoin proof of work scheme.     Mastercoin, NXT, Bitshares and eMunie don't even come close to this kind of security.

Furthermore, each coin is dirt cheap, so using is as a platform for Colored Coins makes more sense.

Anyway, keep informed with iXcoin developments at www.ixcoin.co