Ripple's market cap is not justified in my view. Huge over supply of premined "coins".
There is no proof-of-work, so no mining (therefore no pre-mine). Doing "consensus" instead of proof-of-work is what allows ledgers to be validated every 5-10 seconds without paying massive hardware and electricity bills. Furthermore, instead of coin supply increasing through mining, total coin supply is decreasing since all transaction fees paid get destroyed. Which increases the value of all XRP holders (instead of just benefiting miners).
Consensus is just another fancy word for centralization. For Ripple to work, it MUST have an authoritative ledger. That requires the majority of the network to be trusting the same validators (opencoin inc + bitstamp).
And for bitcoin to work, the majority of the network must all be on the same blockchain. Which means that the biggest mining pools must decide which version of bitcoind they trust enough to run, otherwise the chain will fork. With ripple, the biggest gateways make the decision on which ledger they will be on by choosing which validators they trust.
Your argument is like saying that bitcoin is centralized because everyone has to be on the same blockchain. Bitcoin is decentralized because there is no central authority which can seize your coins (same with ripple).
Ripple is a centralized payment service with a federal reserve (being OpenCoin Inc). It doesn't matter how they word it - if the federal reserve printed 100 trillion dollars but will only release drops through the economy to further their agenda, it's the same as printing money
Essentially the same argument has been used all along by bitcoin detractors - that bitcoin mining is a high-tech pyramid scam to print useless e-currency and then sell it for real money, with the end goal being nothing more than to enrich themselves.
That fact that ripple is backed and bootstrapped by a for-profit corporation is, for some, a bitter pill to swallow. I'm not exactly thrilled about it, but I see how it could have benefits over a non-profit community-driven open-source-from-the-start technical project: paid developers (no need for donations or separate employment), simple and transparent profit model, cohesive and unified marketing strategy, etc.
Furthermore, for anyone to claim that they will refuse to buy shares because its a for-profit corporation, in order to be consistent they must be completely divested from AAPL, EBAY, GOOG, etc. There's basically no difference from buying XRP and buying stock shares in any of those companies (except that the shares of XRP have a hard-coded total cap in the protocol, are continually decreasing in number, don't come with a bunch of wall street shenanigans and requirements, etc). For the time being, I still live in the real world, not an anti-capitalist participatory inclusive utopian democracy. Either swallow the pill, get dragged onto the train kicking and screaming, or get left behind.
