It will be located in Nusajaya, which will be the new admin city instead of Johor Baru. Nusajaya is part of a larger area known as the Iskandar Project.
A model of Nusajaya with LEGOLand Malaysia (top middle)
Another model, with LED lights at night
Here are some work on the LEGO models for LEGOLand Malaysia, made in LEGOLand California by LEGO designers there.
You can read more about this professional LEGO model designer at her blog here.