Latest Answer: In my Opinion.. We are reaching a Point of Saturation on Price. This will get corrected in next 1 - 2 years. Right now what's happening in Chennai is really a Hype due to the Brokers trying to pursuade a higher price than what it is worth off & property Sellers are also bit Greedy (Not all).
What's happened in BLR is not far for Chennai. Chennai very soon the Premium locations would loose its Appreciation effect & stagnate as the affordability may not be there going forward. As most of the Large Scale Factories, Manufacturing & BPOs are moving outward. This Price Trend in Reality will reverse soon.
Balaji