While the Libyan Revolution was admirable, it doesn't appear as though the revolution actually worked. Very few changes have been made since the revolution ended, and it seems like the revolution failed miserably. Libya is barely better off than before the revolution, which has been made apparent by the civil unrest.
Yes, the Libyan revolution seems to have failed, because there is no more freedom in the country than there was before. Rather, there are fringe political groups that are willing to resort to violence in order to get what they want. This was seen in the attack on the U.S. Embassy. The revolution has not enacted any of the goals of peace and freedom.
When a government is overthrown in a country that's barely holding itself together as it is, it almost never thrives afterwards. Everybody that's long wanted a piece of the power tries to grab it, most with bad intentions. Add that in with there being a lot of open space in Libya for people to hide out and plot things and you have a bit of an issue, it's not surprising.
The revolution in Libya was a success because the people got to choose their leader. After years under the dictator, Gadaffi, the people were able to establish a democracy. Although the country is still undergoing a transition, it is clearly in a better state than it was under the dictator.
Most revolutions are very bloody, messy, and take decades to settle down. It is not fair to judge the revolution a success or failure so earl in the game. The United States also had a civil war after it's revolution, albeit much later. They did oust a horrible dictator, so it was a partial success at least.