From flyertalk the list (unofficially) seems to be:
ACC -Accra, Ghana
AMM - Amman, Jordan
CAI - Cairo, Egypt
CMN - Casablanca, Morocco
DOH - Doha, Qatar
DXB - Dubai, UAE
IST - Istanbul, Turkey
KWI - Kuwait City, Kuwait
LOS - Lagos, Nigeria
JED - Jeddah, Saudi Arabia
RUH - Riyadh, Saudi Arabia
AUH - Abu Dhabi, UAE
ADD - Addis Ababa, Ethiopia
However, this is unofficial, I don't think the US government has confirmed what is going on.
Electronics to be banned inflight from 13 countries to U.S. - FlyerTalk Forums