Strategy Page has the details:
Because of budget cuts, the U.S. Marine Corps is losing four (of 27) infantry battalions and twelve (of 70) aircraft squadrons over the next five years. About half the marine aviation squadrons operate transport helicopters. Most of the fixed wing squadrons are bombers and fighters.
These cuts will result in jobs for 20,000 marines being eliminated, shrinking the marines to 182,000 personnel. Most of the units lost are from marine bases on the east coast. The Pacific, and China, is seen as the focus of Marine Corps attention in the future.
In effect the marines will lose nine percent of their personnel strength by the end of the decade. The marines want to do that without losing their most experienced and effective people. The idea is to keep officers and NCOs best able to expand the corps in the event of a national emergency, while at the same time maintaining, for as long as possible, a force that has lots of combat experience.