The fesitival of lights this year will treat Kollywood with two biggies possibly. Ajith and Arya's "Aarambham" is currently hot in Post-Production while not far away is Kamal's much awaited sequel "Vishwaroopam2" which is 90% complete.
Rajini's Kochadaiyaan though has no further updates on an official date, the unit will definitely look at Superstar's birthday 12-12-13 to have a gala opening. If all goes well, Diwali will sport the clash of movies : Ajith vs Kamal, however no official confirmation is out yet.
The rest of the movies which already are lining up this September will try and look for dates before Diwali paving way for the giants. They include Irandam Ulagam, Varuthapadatha Valibar Sangam, Biryani, All in All Azhagu Raja, Vaalu, Nayyandi and so on.