Improving Veterans' Reemployment Act of 2007 - Requires the Secretary of Labor to include, in a currently-required annual report to Congress concerning the enforcement of veterans' reemployment rights: (1) the number of cases reviewed by the Secretary of Defense under the National Committee for Employer Support of the Guard and Reserve of the Department of Defense; and (2) the number of cases which are disability-related. Directs the Secretary to: (1) ensure that the information required to be submitted is categorized in a uniform way; and (2) also submit all reported information to the Secretaries of Defense and Veterans Affairs, the Attorney General, and the Office of Special Counsel.