Decentralization is exaggerated especially after Mtgox disaster. Centralization exchange will be the most people's choice for now and future. It is just like stock exchange center
Decentralization exaggerated??
Decentralization has always been a central selling point of Bitcoin and block chain technology in general.
Stock exchanges and other things like shopping malls etc. are centralized for historical reasons. In the past, space and time were strong constraints for market efficiency and the best solution was to put everything in one place since this minimized the cost to connect market participants.
However, in the internet age nobody needs this kind of centralization.
Bitcoin an other cryptocurrencies will use decentralized exchanges in the future, but one should not assume that centralization is gone or bad per se. Think of the network as a starting point, the network is the place where everything is happening and the network as a whole will be the "place" of centralization but there is decentralization within the network.
Similar thinks are true when think about power and control.
But for Ripple the power within the network is extremely concentrated in the hands of ripple labs which basically controls "everything" there is no ripple without ripple labs, so I think there is too much centralization within ripple.