Since China wields veto power on the United Nations Security Council, no serious multilateral sanctions, arms embargo, or effective military intervention can happen. A NATO or US-backed no-fly zone would inevitably mean occupation, since securing refugee corridors from the can't be done from the air. It would also polarize the region, further align the US against both Muslim and Chinese interests in Africa, and escalate tensions without addressing China's fundamental motivations.
Darfur has become a five-year slaughter because of the failure of the West to devise serious incentives for China to bring Khartoum and the rebels to the table. Direct approaches to Khartoum to find a political solution have been a travesty and cannot succeed. The only way to get the Khartoum government under control and resolve this humanitarian crisis is to enlist China's economic and strategic self-interest – directly.
The West must create a context in which China's self-interest could be better served by reinforcing the rule of law in Darfur. Right now, China handles security on the ground in its own way: Thousands of the oil workers in the fields are Chinese military capable of defending installations there, should rebels gain momentum or the Bashir regime be overthrown.
To stop this surrogate standoff, the West must vest Beijing explicitly in a legitimate form of stability and security in the Sudan – one that doesn't threaten its oil interests.
Rather than attempts at embarrassment, sanctions, threats, or a serious military intervention that China would interpret as a challenge to its control of the oil fields, the focus should be on tying diplomatic and economic efforts together coherently, to enlist China constructively.