They're not a right-libertarian, no. They're an anarchist, I recall them talk about Kropotkin being a huge influence in interviews.

If you're talking about the Libertarian Party, they have a socialist caucus. In fact, socialists called themselves libertarians long before US capitalists did. [more info, second paragraph] But also, see Jerbil's reply about constantly switching political parties, I certainly wouldn't take their party association as endorsement.