The fact is that you can't transact separate currencies which are on separate protocols, unless you represent one as an issued-asset on the other. Colored Coins use the native currency of its protocol - bitcoin. The developer of the first colored coins client, Stefan Thomas, moved on to become CTO of ripple. Ripple is a new protocol altogether, with advantages over extensions/overlays on the bitcoin protocol, the main ones being no mining and much quicker ledgers.
User-issued assets on ripple have a customizable transit fee which is effectively collected in the issued currency (since the fee is paid from the balance of the issue back to the issuer). For example, bitstamp's issuer fee is 0.2%, so any trades of bitstampBTC or bitstampUSD pay 0.2% of the amount back to bitstamp's issuer address. (the fee is set at creation of the issuing address and can't be changed later).
This is not true. There are mechanisms for cross-chain trade, and with a few small changes theres quite a bit more that you can do. See the smart contracts page of the wiki, and the freimarkets whitepaper for example.
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The fact is that you can't transact separate currencies which are on separate protocols, unless you represent one as an issued-asset on the other. Colored Coins use the native currency of its protocol - bitcoin. The developer of the first colored coins client, Stefan Thomas, moved on to become CTO of ripple. Ripple is a new protocol altogether, with advantages over extensions/overlays on the bitcoin protocol, the main ones being no mining and much quicker ledgers.
User-issued assets on ripple have a customizable transit fee which is effectively collected in the issued currency (since the fee is paid from the balance of the issue back to the issuer). For example, bitstamp's issuer fee is 0.2%, so any trades of bitstampBTC or bitstampUSD pay 0.2% of the amount back to bitstamp's issuer address. (the fee is set at creation of the issuing address and can't be changed later).
This is not true. There are mechanisms for cross-chain trade, and with a few small changes theres quite a bit more that you can do. See the smart contracts page of the wiki, and the freimarkets whitepaper for example.