yes, it is supposed to be biggest than Jusco kepong, as from rumours it is supposed to be the 2nd largest AEON mall in malaysia, only after Bukit tinggi Aeon, and the size shall be quite big as it has cinema too. But, I believe if a mall of this size is built in older residential development, the traffic will be bad, but... it shall not be an issue, considering this is a new development, and the road will undergo 3 phase of road upgrades, now is only the first phase, the most will be temporary congestion during road upgrades  There is also a bridge connecting Emerald east and west that is completed, and shall be opening? once that is open, residence in Emerald west/Anggun can travel to east, and exit to the toll that is only about 500m from the Emerald east side. 
I guess no worry... new road will usually be good, definately wider, and better than now, even for 1st phase upgrade
BDRB = bandaraya development berhad    a heavy weight developer shaping bangsar, permas jaya in johor, and also the many award winning "THE TROIKA", supposed to be the most expensive high rise residential in Malaysia, designed by a famous designer Foster and Partners. This shall not be comparable as high end as "The Troika" for sure, but BDRB has always been a premium developer developing high end homes and township. This will be a JV development in the pipeline on a piece of land owned by Magnum beside Anggun, with Guocoland, Hongbeeland, and Bandaraya development berhad on this area... this area will be different, if not flying

http://www.iproperty.com.my/news/3557/BRDB...-strategic-land