Endangered Species Compliance and Transparency Act of 2007 - Requires the Administrators of the Bonneville Power Administration, the Western Area Power Administration, the Southwestern Power Administration, and the Southeastern Power Administration to provide: (1) estimates of each customer's share of each Administration's direct and indirect costs for compliance with the Endangered Species Act of 1973 in monthly billing statements; and (2) an annual report estimating such costs (on a project-by-project basis for the Western Area Power Administration and on a system-wide basis for the other Administrations) to the House Committee on Resources and the Senate Committee on Environment and Public Works.