Premier Rides, known for their selection of coasters and thrill rides, has announced that they have been contracted to build the world's tallest indoor coaster at the Great Mall of China. The "super launch coaster integrates many exciting and unique elements, including Premier's advanced magnetic drive technologies."
While no other details are being release at this point, the coaster itself will be manufactured in the United States and shipped to China. The Great Mall of China is a 76 acre project that incorporates commercial venues, an indoor theme park, water park, and other forms of entertainment along side of retail and dining locations.
It is a little tough for me to be 100% on this, but I believe that Mindbender at Galaxyland Amusement Park is currently the tallest indoor coaster, at 145 feet. That means that the new Premier ride would be taller than that, quite a good size!