Rdio users in the U.S. have just been given a huge gift: free music streaming privileges.
The streaming-music startup announced its free, on-demand music offering Thursday, touting it as the only ad-free, zero-cost plan available in the U.S. market.
Members can now stream any of Rdio’s more then 12 million tracks free of charge — until they cross an undefined threshold for the month. A green meter atop the user profile will track usage and give the user a visual, albeit mostly ambiguous rendering of how much free streaming she has left each month.

