I am not sure if this is a new feature but a friend just noticed a popup highlighting this new feature in his Gmail account.
Gmail’s official list now include India with following carriers supported:
Aircel
IDEA
Loop Mobile
MTS
Reliance
Tata DoCoMo
Tata Indicom
Vodafone (Delhi, Mumbai, Kolkata, Gujarat, A.P, Bihar, W.B. & A & N, Assam, N.E.)
As you can see, airtel is not on the list right now.
Google offers a limit of 50 sms per day. If you receive a response to your sms, it adds five to your daily quota.
This feature did not work for my friend when he tried sending me a sms. Could be somehow related to DND as my number is in that database.
Please leave a comment if this feature appears on your Gmail account and works!