What is the center of the Bitcoin universe? With a completely decentralized digital currency like Bitcoin, it's hard to say, but today, Silicon Valley took a serious step toward claiming those bragging rights.

That's because one of the Valley's most important venture capitalist firms, Andressen Horowitz, made the biggest bet yet on a Bitcoin company, dropping $25 million on Coinbase – a company that's trying to make it easier for consumers and merchants to use the digital currency.

It's the largest-ever investment in a bitcoin company. And it's a sign that bitcoin may be becoming a Silicon Valley phenomenon. "Bitcoin is going to be as big as the Internet," Andressen Horowitz's Chris Dixon told The New York Times today.

Bitcoin already has an active community in New York City, the country's financial capital. That's where early companies such as BitInstant and Coinsetter started. But lately Silicon Valley has been making a serious play for Bitcoin.

Investors such as Accel Partners, Lightspeed Ventures, Adam Draper's Boost accelerator, and now Andreessen Horowitz have all jumped on board. In Sunnyvale, there's another Bitcoin accelerator, this one run by a business incubator called Plug and Play.

It makes sense, if you think about it. Bitcoin has captured the hearts of New York financiers as a digital currency. But Silicon Valley types can also relate to it as a new kind of open-source software platform. The bitcoin system is run software spread across a worldwide collection of computers run by whoever wants to run one.

Which will eventually win out – New York or Silicon Valley? Which will become the U.S. home of Bitcoin? "There has always been a little bit of tension between Silicon Valley and New York," says Joshua Rossi, the founder of New York's open-air, ad hoc Bitcoin marketplace, called Satoshi Square. "Bitcoin – in some ways the perfect marriage of finance and tech – is going to struggle to find a home."

Over in New York, things haven't been helped much by the New York State Department of Financial Services, which in August subpoenaed a Who's Who of bitcoin investors and companies, asking them about their bitcoin activities. Both Andreesen Horowitz and Coinbase were served.

But in Sunnyvale, at the heart of Silicon Valley, Scott Robinson says that while New York is a great place to find people who know the financial industry and its regulations, things have shifted recently, "with more experienced software guys looking hard at entering the space." That helped San Francisco's Coinbase, which recently hired Google's Charles Lee to help with development.

Silicon Valley gets the nod because of its deep pool of software developers and because it's home to "the type of investor willing to throw money at a virtual currency," Robinson says. But don't write off New York just yet. "NYC won't go down without a fight," says Rossi.