At Dawg's there's discussion of the intervening under the legal concept of Responsibility to Protect (R2P). This would likely mean the intervention by the liberal West, given that much of the rest of world doesn't subscribe to international liberalism of have it's socio-political history.
There are two big problems I see with intervening.
The first is purely practical. Libya is fast changing. It's only been a few days since things really began and the situation on the ground is very fluid. It takes time to form an effective intervention force. Even airstrikes on airfields and identifiably hostile military units (the armed forces appears divided at this stage) take a significant amount of logistical planning to be conducted effectively. If Libya has an effective air defence system, the task becomes more complicated. The dust may settle long before the first NATO fighter-bombers spool up. Or, the planning staff tasked with assessing Libya will determine that there is simply no effective means of intervening with a chance of success. An in and out mission sounds feasible in practice, but the recent history of such things is replete with retrospective magical thinking and long residencies by foreign armies.
The second is tricksier from a political economy perspective. R2P is a nice sounding idea but it is the product of a Western liberal internationalism that also relentlessly pushes neoliberal globalisation with a history embracing shock-doctrine methods to impose it on states in crisis. I do not trust the busybodies in the international community, if it turned out to be feasible to go in under R2P, to refrain from finding a way of imposing economic reforms and/or attempting an Iraq or Afghanistan do-over because they think they know what they got wrong in those places. Who do you think they'd hire to 'help' the Libyans transition? There's legions of experts now with experience helping a post-tyrant petro-state 'reform'.
Egypt, Bahrain, Tunisia: these are their revolutions and so far successful ones at that. Yes there is blood, yes Gaddafi as proven himself monstrous despite Tony Blair's assurances. Yes, our humanitarian concern is valid. But until the West, even in decline as it is, can separate itself from its current ideological framework, we ought to refrain from inserting ourselves in someone elses revolution. Our intent may be pure, but our approach is
These are so far successful revolutions by motivated and fearless people. Blood though there is, I do not feel that they are in need of anybody's help internally until they ask for it or until it looks like the regime maintains enough force of arms to crush it. After the last decade, the last thing any Arab or Muslim state needs is for the West to come galloping in to save them from themselves. If viable new states are now in birth from their own people, they ought to be able to own their origins and not have to put up with the old colonial powers forever patting themselves on the back for saving them as they sell them coca-cola and lift their natural resources.
We can help them in different ways. These revolutions are fundamentally about [in]justice. People aren't being gunned down in the streets of Tripoli because they want their state to be competitive on the global market and host the World Cup. They are dying because they've been living under a tyrant for forty years. They've been disappeared, beaten, tortured, bombed, and denied the opportunities that real freedom allows. The best thing that we in our liberalism can do is help them find justice in the aftermath. We can support actions through the International Criminal Court, honour extradition requests for fleeing ministers and generals, seize assets, and provide resources.