This is a welcome move (and I am late to join the thread) ! What I feel is, more than the 'green' factor, this has to do with the declining sales figures. Beat has not done as expected for GM; not only in India but also in Europe. Ritz has done considerably well in Europe; however it is still trying to find the rythem in Indian market (read the very important market for Suzuki). The same goes with SX4. Considering the dent made by FIAT, Hyundai, Ford and TATA (yes TATA), MSIL is left with no other choice. Having said this, we have to accept the fact that CNG / LPG is more green and cheap to run.
PS: I am trying to locate the news about the wide usage of CNG and CNG stations across India. There was some move like this last year. But I am unable to locate. If you guys happen to locate it, please post.