From the announcement:
The Office of the Federal Register (OFR) and the Government Printing Office (GPO) are moving the Federal Register Home Page and the Public Inspection Desk to www.OFR.gov. Please reset your bookmarks before July 26, 2010. This change is necessary to make way for a new edition the daily Federal Register, an unofficial “Web 2.0” prototype, which will be hosted on FederalRegister.gov.
The Federal Register Home Page on OFR.gov will continue to feature the electronic Public Inspection Desk, the Privacy Act Issuances for 2007 and 2009, and the OFR Catalog, which links to all Federal Register publications and services.
As of July 26, 2010, the FederalRegister.gov website will display an XML prototype of the daily Federal Register. It is not an official legal edition of the Federal Register, and does not replace the official print version or the official electronic version on GPO’s Federal Digital System. OFR and GPO are posting the unofficial XML prototype of the Federal Register to gather public feedback, with the aim of granting it official status in the future. It will remain an unofficial informational resource until the Administrative Committee of the Federal Register issues a regulation granting it official legal status.