Change is occurring though. ROC President Ma Ying-jeou (KMT) announced the PRC will no longer stand in the way of ROC having observer status in the World Health Assembly, which is a branch of the United Nations. The catch is the ROC will have to use its Olympic Gamesname of Chinese Taipei. (Hat tip: Weekly Standard)
The gesture is the PRC's way of allowing the KMT to show cross-straight talks between the two governments work. This should give the KMT more respect when it comes to elections. The PRC wants the KMT to stay in power because the KMT is willing to negotiate into somesort of union/confederacy with the PRC. These efforts have been successful to the point of joint-military talks between the two Chinas.
The PRC fears Taiwanese voters will become tired of the KMT and vote the DPP back into power. This would lead to renew tensions between ROC and PRC. The PRC wants the Taiwan/ROC issue settled. Too much time and resources are put into the issue, Beijing thinks. Once it is resolved the PRC can shift attention into expanding its sphere of influence in Asia and Africa more.
Meanwhile, the ROC is content in returning to the United Nations since its exile in whatever form it is allowed to.