The US Government has forbidden government personnel from visiting the Old City of Jerusalem on Friday, and is restricting their travel within Judea and Samaria too (no information if that restriction also includes Jerusalem neighborhoods such as Gilo and Har Homa).
The US also recommends that all US citizens stay far away from (presumably Arab) demonstrations today, as they expect they may get violent.
Consulate General of the United States of America
JERUSALEM September 14, 2012
Security Message for U.S. Citizens: Possible Demonstrations in the Old City
The U.S. Consulate General in Jerusalem advises U.S. citizens that due to the possibility of demonstrations on Friday, September 14, the Old City of Jerusalem is off-limits to U.S. Government personnel that day.
U.S. citizens are advised to defer non-essential travel to the Old City and to generally exercise an extra measure of caution.
We remind U.S. citizens that due to the possibility of demonstrations throughout the West Bank, the U.S. Consulate General has limited both official and personal travel in the West Bank until further notice.
U.S. citizens are advised to defer non-essential travel to, and within, the West Bank and to exercise an extra measure of caution.
We also take this opportunity to remind U.S. citizens that demonstrations, even peaceful ones, can turn violent with little or no warning. U.S. citizens should be aware of their surroundings at all times, and avoid large crowds.