Darfur

Wow,
I now know more about Sudan and Darfur then I thought possible.
Okay lets leave oil out of this for the moment. I think oil is being coming the cliché reason nowadays.
Your friend is right on many points I believe. The number of rebel groups is kind of hard to pin down because they seem to be changing all the time. Basically what we have in Darfur is a reaction to rebels trying to take down the government in Khartoum. The whole thing is kind of complicated but I will try my best to convey what I have just taken in.
The rebels are farmers. They are pro-Chad and pro-Eritrea. They are Islamists in nature. They may or may not be led by a former ally of Bin Laden's, Hassan al-Turabi, more on him later. From what I can tell though they, the victims, basically started it. They attacked the government first in an attempt to overthrow it.
The Government was humiliated numerous times by the rebels and they got pissed. So they unleashed hell on the rebels. At first the Sudanese Government wasn't prepared to fight in the desert and the rebels, like most insurgencies exploited that weakness. Typically though governments catch up and go overboard. Think Serbia's reaction to Albanian rebels in Kosovo. So during the start of the conflict the government was only able to punish the rebels with vicious air raids.
In Sudan there was already a long time animosity between the farmers and the Arab nomads. The fact that the nomads are Arabs and the rebels are Islamists kinda fucks up the whole Arab/Black narrative. There has been a long drought in the region and as a result there was very little cultivatable land to be had. So the farmers and the nomads had to battle it out for land.
Since there were already problems between the farmers and the nomads, who had been previously armed by Quadaffi (Sp?), it wasn't difficult to rally them in support of the government against the rebels. These nomads became the Janjaweed. The Sudanese government armed them to the teeth creating a paramilitary force.
I have a hard time calling this genocide in the classic sense as does the UN. It really seems like impropriate force and massive war crimes. To me genocide is more like the Jewish holocaust, where an entire ethnic group is systematically being exterminated. This is simply not happening in Darfur. Yes it is ugly, terrible, and should be stopped but it is not genocide. It has the appearance of genocide. The refugees fleeing into a neighboring country, a perceived ethnic difference, villages torched and children being slaughtered.
OK, western intervention, the Government of Sudan is not cool to the idea that Western troops coming into his country. This is why to date the peacekeepers have been Africans. Sudanese President Omar al-Bashir, is fearful of the fact that he is a war criminal and does not want to be arrested by Western Forces. So he will not agree to a western force.
Now on Bin Laden and the supposed rebel leader Hassan al-Turabi. After the Iraq invasion of Kuwait Bin Laden lobbied the government of Saudi Arabia to bring an army of the mujadeheen (sp?) to expel Saddam from Kuwait. The government instead allowed the West to intervene and station combat troops in the Arabian Peninsula, one of the reasons given by Bin Laden for 9/11. Bin Laden was invited to Sudan by Hassan al-Turabi. Osama actually married on al-Turabi’s nieces. In return for protection, Bin Laden spent his money building infrastructure.
Al-Turabi has connections to the Muslim Brotherhood as do most influential populist Islamists. He rose to power in Sudan and became the second most powerful man in the country. Of course, if the second most powerful person gets too popular the most powerful man usually takes action. That was the case here. Omar al-Bashir arrested al-Turabi as a threat to Sudan and imprisoned him. He was then released in 2003 and teamed up with the main rebel group at the time, the JEM, Justice and Equality Movement. He of course denies this.
I have had a hard time finding any information about oil in the Darfur region, which is not to say that the information isn’t there or that there is no significant oil supplies in Western Sudan. From my own old recollection oil is a factor mainly because the government is oil rich and the Chinese, with Security Council veto power, get oil from the country. Bin Laden believes that the call by the west for action in Darfur is cover for a takeover of Sudan and its oil wealth, kinda like Iraq. I think that many distrust the West for good reason. Anyone who doesn’t think that the War In Iraq pt.2 is about oil is either stupid or in denial. I also do believe that the West has been creating a new form of colonialism in the form of capital control.
I hope that was helpful. I didn’t really know anything about the conflict because there are just too many shitty things happening all at once all over the globe and it is too hard to pay attention to all. Over all I think your co-worker may be right on a lot of it.
Here are some of my sources I used.
Human Rights Watch
Images of War Dead
London Editorial from Tawianese Paper
Wikipedia