Those files are free to use.
(If you'd like to know how to install the data files, read here.)
Status: "Dominion" (base game), "Intrigue", "Seaside", "Alchemy", "Prosperity", "Cornucopia", "Hinterlands", "Dark Ages", "Guilds", "Envoy (promo)", "Black Market (promo)", "Stash (promo)", "Walled Village (promo)" and "Governor (promo)".
Recent changes: 2013-10-29 (version 1.1): Fix price of "Nomad Camp" card.
Status: "Tanto Cuore" (basic set), "Expanding the house" and "Romantic Vacation".
Status: "Heart of Crown" (basic set).
Status: "TRAINS" (basic set).
Status: (Japanese only)
Status: (Japanese only)
Status: (Japanese only)
Status: (Japanese only)