General Nkunda has probably been the most powerful rebel leader in the Democratic Republic of Congo. It has been widely thought that he was supported by the government of Rwanda.
Today he was arrested in Rwanda. This is a major development in the DRC and changes the ballgame quite a bit. As a charismatic, well-organized leader, Nkunda was well on his way to controling a good portion of eastern Congo in October. However, he may have overstepped in his quest for power. His military surge brought renewed attention to the conflict in the DRC and pressure on Rwanda to control Nkunda, since many believe that Nkunda's troops have been receiving arms from Rwanda.
With Nkunda out of the way, it isn't clear what will happen next. He has been charged with war crimes in the DRC. Rwanda may extradite him to the DRC to face those charges. It may hold on to him itself. Either way, he is out of the mix. Of course, there are many other warlords and militias operating in the DRC, so peace is still a distant hope. However, it is a good sign that Rwanda and the DRC are working together to bring peace to the region. Let's hope that progress continues to be made.
UPDATE: For those interested in more background on Laurent Nkunda, a good BBC profile can be found here. One by Time can be found here.