Speaking at the ESRI UC Senior Executive Summit in San Diego, U.S. Secretary of the Interior, Dirk Kempthorne, announced that the 35 years of archived Landsat data will be made available over the web free to the public by the end of the year. The EROS Data Center (EDC) of the USGS will be the lead center to implement this initiative. Though not mentioned specifically, it's likely that some of the data may be released through EDC's EarthExplorer portal that was a pilot project begun last year for Landsat 7 data.
Listen to my interview with Secretary Kempthorne and USGS Director Mark Myers regarding the announcement of the Landsat data and a follow up questions I asked regarding the USGS's roll in providing policy-makers information about the Alaska National Wildlife Refuge (ANWR) and offshore drilling. [podcast: "Kempthorne-Myers_final.mp3"]