Amir Taheri breaks down the situation in southern Sudan here.  This part of the Sudan has never gotten the same sort of mainstream news coverage that Darfur has, and certainly has not received the same celebrity attention.  It may have something to do with with the religious make-up of the areas – southern Sudan being largely Christian and animist, Darfur being majority Muslim, but I really have no idea.  Perhaps, as Taheri touches on, there is no convenient name for southern Sudan beyond, well, southern Sudan, whereas Darfur lends itself nicely to media.  In any case, it is a good read.  The situation in both areas deserves our attentiveness and prayers.