Keep in mind that the centralization is not part of the technology platform.
I have no strong feeling about Bitcoin as a currency (but if informed people want to speculate with it, that's fine by me, but they should know what they're getting into), but as a method of creating systems of non-centralized, distributed trust the platform has merit, and I think we'll see interesting things come out of it. IMO the main interesting thing about Bitcoin is precisely this. There is no need for centralization -- in fact, the system works much better without it, as a concentration of computational power actually opens it up to manipulation and other nefarious things (this has to do with how blocks are accepted into the chain, but the specifics of which are probably beyond the scope of a random forum posting).
At its most basic level Bitcoin is a technology that could actually be used to help
ensure that decentralization remains a feature of the Internet. Much has been written about the currency aspect of Bitcoin, but most the folks who are thinking/pondering/working in the space are actually trying to figure out how the technology can be extended to be brought to bear on other, worthwhile problems. When I first got on the Net it was all computer information and NASA sites. The Net became what it did because a lot of people asked "hmm, what else can we do with this?" And that's happening now with Bitcoin. What will ultimately come from it? It's hard to say, and it's possible that the world doesn't really have an appetite for distributed crypto-currencies, but my guess is that some interesting things may come from it regardless.
The centralization you see says more about people than it does about the actual technological platform. As a rough analogy: the fact that Amazon more-or-less dominates the book market has nothing to do with the web's technology and a lot to do with how people buy things and a lot to do with base economics that have nothing to do with "on-line." In theory the net is a democratization of information; in practice this democratization is often irrelevant given our disposition to forming herds.