Chen said he felt "cheated" over the development given that Senegal had "repeatedly promised" that China's economic activity in the country would not affect its diplomatic relations with Taiwan. (Source)
In light of the surprise, officials in the Foreign Ministry and National Security Bureau are now warning of
concern that Taiwan's entire roster of allies would succumb to Beijing's diplomatic clout.
The most likely ally to fall next is the Vatican (Holy See). (On the other hand, I've been predicting that switch for months.)
Details are starting to come out about Senegal's switch:
[Senegalese President Abodoulaye] Wade said that "between countries, there are no friends, only interests."
The price tag for Senegal's switch: 600 million US dollars.
- The Times of London reports:
The Vatican is preparing to break its ties with Taiwan and establish diplomatic relations with mainland China, ending more than 50 years of mutual hostility with Beijing, The Times has learnt.
- ESWN opines that the going rate in Taipei for a diplomatic ally is on the order of half a billion NTD annually (or 15 million USD).
Reply: Sun Bin analyzes Taiwan's diplomatic allies in order to attempt to answer this question.