The original idea for ripple was a credit network based on pairwise trust. The reliance of pairwise trust instead of global consensus gave it a significant scaling advantage compared to blockchain crypto-currencies: if you make a set of trades that can be settled entirely within your local community there would be no need to tell the whole world about them. It would have been possible to use ripple along side Bitcoin in order to get low cost high scale transactions denominated in Bitcoin— which you then periodically and automatically settled with actual Bitcoin.

The ripple system of today is very different: It is a blockchain global consensus system— like Bitcoin, with all the inherent scaling limits— which exchanges pre-mined coins.  It replaces the attack resistant decentralized POW consensus in Bitcoin with a something which is either dependent on centralized trust or, alternatively, is sibyl vulnerable (depending on how  UNL actually plays out— the system basically punts sybil resistance to the user, instead of being fundamentally sibyl resistant like POW systems; my expectation is that sybil resistance is too hard to punt to the user and the effect will that people will only trust a few big nodes— effectively making it a centralized system).

How did it go from a interesting and potentially worthwhile addition to the cryptocoin ecosystem to— what basically amounts to— "just another premined altcoin"? Frankly, the whole things sounds like something RealSolid would have come up with now.