Article: http://www.roller-coaster.com.au/article.php?aid=71

I would be very interested to know just how much excess land is available for future expansion now that DW has sold off a lot of the excess for the retail/residential development. There is obviously still some space left within the park. There is the old Thunderbolt site and the area around the river and Avis vintage cars (assuming they want to build on this site... I'm thinking COASTER supports partly over/in the river might be nice). But it seems like if they have sold off the excess land, then any room for expansion outside the park might be very limited

Sounds like a good commitment, since the money could be split up with some saved (where it could gather interest) with the rest being poured into yearly projects. But 12 million every two years could build a superman sized coaster which could be very cool.