Already those who have been itching for some sort of international intervention in Syria on the Libyan model are starting to argue that the outcome in Libya supports their case.It seems to me that they are very different cases, and that the sort of limited intervention carried out ("leading from behind") in Libya could not easily be replicated in Syria, without far greater risks.
First, a caution about being too quick to draw lessons from Libya: if your sole definition of success is the death of Qadhafi, that has been achieved. But only hours ago: what Libya will look like tomorrow, let alone next year, is murkier. There is not yet much clue about what a transitional government will look like, or even who all the players will be. Before we wish to replicate something, let's find out what it is, first.
Second, though I have no desire to see Bashar al-Asad continue in office, I think it is clear that he is neither so isolated as Qadhafi, nor is his power base so thin. The Alawite community, if not entirely supportive of Bashar personally, fears for its position in a Sunni-dominated governments; secularists, women, Christians, and Druze mistrust and fear an Islamist-based regime, and see that as what many of the protesters, especially in the north, are calling for.
In the end, Qadhafi had no international friends. Asad's allies, Iran and Hizbullah in Lebanon, will likely support him, however much the US may regret that. Even Israel, a traditional enemy, may quietly prefer the devil they know (and have negotiated with) to the devil they don't. And Israel isn't alone in that sentiment.
Also, Libya, with most of the population confined to cities along the Mediterranean coast, is much more amenable to sea-based or European land-based air power, as opposed to Syria, whose major cities are mostly inland, forcing air operations to fly through Lebanese airspace of fly roundabout by Latakia. Not impossible, but more complex.
It is important to remember that the Western decision to intervene in Libya was somewhat spur of the moment, when it appeared as if Benghazi could fall to Qadhafi's forces within a day or two. No such imminent disaster currently looms in Syria.
I hope the Syrian protesters can bring democratic change to that core Arab country; I'm pretty sure it would not be welcome if it were perceived as coming from NATO rather than the Syrian populace. Syria isn't Libya, and we're not even sure what Libya itself is going to look like yet.
As for the other ongoing Arab uprising, Yemen, the US seems to have no enthusiasm for getting involved there, in part because ‘Ali ‘Abdullah Salih helped the US track down Anwar ‘Awlaqi, and in part because of the presence of Al-Qa‘ida in the Arabian Peninsula. It's fairly easy to see the risks of outside intervention there, even for those who want to have a go in Syria.