Yeah, this is pretty crazy. No matter which side you come down on in the Palestine/Israel conflict, there's no way this can be good for the region. Hamas has been making strides to become a legitimate political organization rather than just a terrorist group recently though, so maybe they will realize that the only way for them to truly have any power is politically--not militarily--and back off of the bombings, etc. As I see it there are a couple of definite positives that should come out of this: it will force Fatah to be less corrupt, and this is the first hint at a true, multi-party democracy in Palestine. Of course, there are negatives as well: Hamas will not be recognized internationally (especially by the US and Israel, at least until they disarm...which will never happen), also, although there has supposedly been a year-long truce, Hamas could use their increased power and legitimacy to escalate violence (especially since many Palestinians think violence is the reason that Israel pulled out of Gaza in the first place).
Hamas started out as a charitable/social organization before evolving into a terrorist group...maybe they can revert back to being a legitimate, positive force in the region (but I wont be holding my breath).