Ripple had $2.5B money transfer, now second biggest virtual currency
coinmarketcap.com
coinmarketcap.com
Like: "First of all, the source code isn’t even out yet"
And the multiple issuer issue that is display as "no milestone" has been closed and implemented in the current version of the client.
Ripple is currency agnostic.
I believe Mastercoin and Coloredcoins are Ripple-style ledger on Bitcoin network technologies.
If you'll remember in the early American Colonies, [every colony had its own currency](http://en.wikipedia.org/wiki/Early_American_currency).