Vieques Bioluminescent Bay Conservation Act of 2008 - Designates certain submerged lands and waters of Puerto Mosquito Bay, Puerto Rico, as the Puerto Mosquito Bay National Marine Sanctuary under specified provisions of the Marine Protection, Research, and Sanctuaries Act of 1972. Gives the governor of Puerto Rico veto power over the designation of any part of that area and over the related management plan and regulations. Directs the Secretary of Commerce to issue a comprehensive management plan and implementing regulations.