Yup they still work (US test launches Minuteman III ICBM)

[Statistical]

USAF Conducts Successful ICBM Missile Launch

The United States Air Force successfully sent an unarmed ballistic missile from Vandenberg Air Force Base to several targets located in the Marshall Islands in the Pacific Ocean, government officials said.

On Sunday at 9:01 a.m., the unarmed Minuteman III intercontinental ballistic re-entry vehicle was sent more than 4,000 miles during the latest round of testing, which saw the missile approach speeds of 15,000 mph. Military officials didn't say if the most recent test impacted targets in the water or on land. Tracking and telemetry equipment was installed on the rocket by the 576th Flight Test Squadron, which was in control of the missile launch for the U.S. Air Force.

The US has 450 Minuteman III ICBM as part of its strategic arsenal.

http://www.dailytech.com/USAF+Conducts+Successful+ICBM+Missile+Launch/article16065.htm