In an article on Billboard.biz, it seems there are many in the music industry concerned over the possibility of a .music extension.
From the article:This time, they're taking their case to the National Telecommunications and Information Administration, an agency of the Department of Commerce that is soliciting feedback on new proposed rules for how new top-level domains are granted. ICANN, the entity that administers the top-level domain name process, does so under a contract from the NTIA, and as such would have to follow any new requirements the agency sets, at least for the U.S. market.
Their primary concern was that they wanted direct control over who could register a .music domain name. They don't want illegitimate online music services obtaining a .music domain, basically.
Read the whole article HERE