I have read more about the state of bitcoin regulation in Idaho, and it appears that at least one business has been registered as a money transmitter.
REF:
http://www.mondaq.com/unitedstates/x/277850/Financial+Services/Bitcoin+Current+US+Regulatory+Developments------------
Current State of Regulation
Money Service Business and Money Transmission Registration and Licensing
As of the time of this writing, FinCEN is the only US federal regulator to have released official guidance on the use of Bitcoin. In March 2013, FinCEN published interpretive guidance clarifying the application of the Bank Secrecy Act and the USA PATRIOT Act to Bitcoin and other convertible digital assets by stating that any administrator or exchanger of bitcoins (or other convertible digital asset) must be a registered MSB under FinCEN's money transmitter regulations. The release indicated that individual users of bitcoins that are not operating a business would not be considered MSBs and therefore would not be required to register, report or perform recordkeeping. Such clarification also requires administrators or exchangers of bitcoins to comply with applicable state law and register with certain state regulatory agencies.
Furthermore, various state regulators, including the California Department of Financial Institutions, the Idaho Department of Financial Services and the New York Department of Financial Services, have followed FinCEN's example and have issued interpretations or mandates requiring that Bitcoin exchanges and service providers register and/or seek licenses on a state level as money transmitters or MSBs.