Safety when traveling in Egypt is on everyone's
minds, and after living here six months, this is my take.
As a foreigner, you are precious to most Egyptians,
  and you will be protected. On the other hand, if you
  opt to join protests (like the Tahrir Square protest nearly
  every Friday), your fate rests in your own hands. Carry
  your passport or a copy of it with you. The police and
  military are legally obligated to protect foreigners, and
  your average Egyptian will go out of his way to help
  you. Avoid downtown Cairo on Fridays and whenever
  a demonstration is announced, but otherwise, areas like
  Giza and Saqqara, and vacation cities like Luxor, Aswan,
  Sharm el-Sheikh and Marsa Alam are safe and welcoming.
  Women should remember to wear sleeves, at least
  covering the shoulders, and it's prudent to wrap a cotton
  scarf around your neck in case you need to cover up (not to mention protect you from breezes and sun).
  Some Egyptian men have the idea that western women
  are by definition loose and easy targets.
Sign up for the U.S. State Department's travel alerts,
  and register with its Smart Traveler Enrollment Program
  ( https://travelregistration.state.gov ). Its alerts are more
  paranoid than I think necessary, but ever since it was
  caught with its pants down when it didn't see the
  Arab Spring coming, the State Department has been
  super-cautious. I read the English language version of
  Egyptian papers like Al-Ahram and Al Masry-Al Youm online to see which way the wind is blowing.
I just finished hosting my family here at Christmas,
  and have more family on the way - - which should tell
  you whether I think it's safe here.
- - A.E.L.