One of the differneces between Ripple and Bitcoin is Ripple was never designed to be a currency, it's designed to facilitate movement between currencies.
The supporters of Opencoin's Ripple keep saying that, but I do not believe this is true. Opencoin states that they wanted to use the XRP they gave themselves to serve as their own payment for developing their version of Ripple. This would not make any sense if Opencoin did not expect XRP to actually become worth enough to serve as a currency. Also, who cares what they were designed for, when reality shows that they obviously
are being used as currency.
I keep repeating myself, but XRP seems to me like the potentially biggest premine scam ever pulled off: 100% of the XRP for themselves, and if they have a good day, they may stick to their promise of distributing them in a fair manner. Personally, I am not willing to give a for-profit company enough trust to expect this to really happen.