It will depend on the individual site but its more Havan/ Butlins/ Pontins than Centre Parcs. Each site is often run independantly, the one we stayed on in Spain had Canvas and Eurocamp as well as its own bungalows and hundreds of tourer spaces.
The pool was nice but the entertainment was of a pretty low standard, not that we were that bothered about that but even Butlins could put on a good show. ( The bit where the guys on stage were pretending to hold there bits out of there trousers was the signal it was time to go home and this was the first song of the family show. 
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Every thing else was very havan like the table tennis tournament and hourds of teenagers roaming about looking for something to get up too. There was a kids club but I wasn't interested in watching my kids doing jigsaws all day. Club was supervised but not enclosed.
The caravans were set out quite nicely but very close, they were end to end so unless you closed all the curtains you could see everything in all the caravans in the row, Plus the \link{http://www.mumsnet.com/Talk?rn=63990&topicid=1700&threadid=183111&redir=63990\caravans} behind were close enogh that you could hear every conversation and chair moving. I wouldn't have fancied the tents much either as they were very close and you know what it is like under canvas, no secrets.
It was a lesson learned for me and I would rather book direct with the sites and stay in there accomodation, which at that site was lovely thatched bungalows.