I wouldn't expect it till 2012 or so, unless this is part of the next coaster project. This would be one of their "big" projects, which are usually more spaced out, though they have been expanding so rapidly lately.
I'm sure an area like this would cost a good $15 million plus. The area needs to be cleared out and leveled right (though I hope they don't go too far and build around the natural setting, like in other areas of the park, then the infrastructure has to be extended out there, new service roads and utilities set up, and it would probably warrant some type of large attraction or attractions.