It's definitely capitalist. It's sometimes referred to as "capitalism with asian values" or more correctly "authoritarian capitalism". It's happening right now and it's sadly more effective than western liberal capitalism.
The communists - if they were actually communist - surely wanted the people of China to prosper. The past leaderships of China, I'm really not sure about but it seems pretty clear that the "current prosperity" you're referring to isn't prosperity of the people in general.
A state that prospers without [almost] all its people prospering would appear to contradict with communist notions of state; so perhaps this is just indicative of China being a capitalist economy now with some central planning (like the UK, say!?!).