Well, it could have been called "network resource allocation units", "secure stamps", "reusable proofs of work" (like its competitor, RPOW), or any number of other such techno-jargon and flown under the regulatory radar for a while.   Of course, it would be rather difficult to market it is a payment system using such euphemisms.   Who's using RPOW, for example?

But ya wanted to market it as, you know, _money_, so the cat's out of the bag.   It's  called "Bitcoin" and people are using it to "pay" for things.  So it's obviously a financial system (for purposes of e.g. money laundering regulations and similar restrictions).   But because it's not a government currency it's not "money" for the UCC.  So for example in the U.S. you can't write a check for "10,000 BTCs", it won't be considered a legal negotiable instrument.   So you get almost all the financial regulation, which will regulate it as money transfer, but not the respect of the UCC, which will just treat it as an ordinary good (or possibly even a service, putting you outside the UCC and into common law)  if you write it into a contract.  (Caveat: I am not a lawyer, folks who are seriously using this stuff should consult real lawyers).