So what's the legal interpretation of this?
a person is an exchanger and a money transmitter if the person accepts such de-centralized convertible virtual currency from one person and transmits it to another person as part of the acceptance and transfer of currency, funds, or other value that substitutes for currency.
What are the implications of being an exchanger and money transmitter?
They who transmit Bitcoin as part of the acceptance and transfer of currency, funds, or other value that substitutes for currency will conceivably have to get registered. There's a reason bitcoin-central.net is pretty much the only functioning exchange at the present time.