People in Libya and other Middle Eastern countries are dismayed and upset about the attacks on the consulate in Benghazi and embassy in Cairo. A collection of Tweets about the attacks (some translated from Arabic) can be found on a website called Global Voices.
I think it's important to reject any implication that what happened is in anyway similar to Tehran. The Libyan government has condemned the attack, and it is not supported by most Libyans. (I can't verify this with a poll, but there doesn't appear to be a general anti-American sentiment.)
Beefing up our marine units in Libya and Egypt is a prudent measure, but any other military action would seem to be unwarranted. Ambassador Stevens lost his life in a country he had spent a lot of time in and probably had great hope for Libya's rebirth. I hope the Libyan government can keep any further protests from going out of control so that there will be no more waste of human lives.
Some sample Tweets:
@Khalil_alagha: The American Ambassador who was killed in Benghazi was a strong supporter of the Libyan revolution and he loved the Arab world. His reward was his murder. We are a doomed nation.
From a Saudi
@Fahad: No one is more dangerous than someone who has religious zeal combined with ignorance. The Libyan revolution will lose its credibility if the criminals who have killed the American Ambassador are not punished.
From Egypt
adiaE: We truly deserve all that is happening to us. The whole world will despise us until we get rid of the ignorance and fundamentalism we are in. There is something wrong with us and not with a stupid movie.