National Visa Center who processes the Visas for the applicants. NVC is currently processing June 2001 for the category of Brother and sister of the US Citizen (F4), 12 years behind from today's date. Your brother has to maintain the status if he wants to stay here until he gets a green card. Best of Luck. BWT, he probably gets a green card around age of 50 if he is 38 now.
http://www.travel.state.gov/visa/bulletin/bulletin_6028.html