Yeah, I think Shrek is opening in September and Superman in Decemeber. Decemeber January are peak summer months down here (proabbly Feb too, Rabid would know more accurately) - so having it open in december would make sense I guess. Having said that, September school holidays are huge, so maybe that is why they are getting Shrek ready to open in a couple of weeks. From what I have been told, most of the ride system for Shrek has been installed...
Edit: Slightly off-topic, but it get mentioned on our boards recently and I think a lot of people agree. I really hope movie world upgrade the ride program for Batman the ride (motion simulator). The CGI program they have in there at the moment, whilst enjoyable, could be so much better.