Salah Khalaf would be the most likely figure to take over from Arafat, but seeing as he was taken out by Abu Nidal in the 1990s, and possibly even more inclined to a two-state solution than Arafat, he might have been assassinated soon after. Perhaps the more left-leaning (Marxist/Communist) less pan-Arab, rejectionist factions within the the Palestinian movements gain ground? Abu Musa could become viewed as the leader of the Palestinian movement. With the prominence of rejectionists the OTL Hamas syle non-recognition of Israel could continue - Hamas might be a minor faction in Palestine.