Just got back from Thorpe Park. I've been reading the posts about Opening 'thrill chill' day, and I am glad I decided to go a few days later this year. Everything was open, as far as I know, at 10am except for Colosus and Rush. Colossus opened around 11:30 and Rush never opened (someone told me that it did eventually, but I never saw it myself), but it was advertised that Rush would be closed before entering the park.
No complaints from me about 'Thrill Chill', managed to get on everything that was advertised for about half the price. Last year and from what I've read, this years, opening day wasn't too great, but today was brilliant, got to see some progess on Saw and minimal wait times all day too.