Taiwan, that's who. The announcement cannot be a surprise, but the parallel is creating a stir in Beijing:

[Taiwan's spokesman] Huang said that Taiwan is a country which upholds democratic values and is pleased to see Kosovo attain independence and the fruits of democracy. He said that contact between Taiwan and Kosovo has been very positive so far. Observers say however that Kosovo may face similar problems to Taiwan in its attempts to join the United Nations. Whereas Taiwan faces pressure from China, Kosovo's sovereignty is rejected by Serbia and Russia."

Kosovo likely won't be able to return the favor. Only a few hardy souls still recognize Taipei and the number is dwindling as Chinese economic and political might grows.