I've yet to see a Spotify employee around these forums. And unless someone working for the company will register here and accidentally stumble across your post, your question will most likely remain unanswered.
You could go to www.spotify.com though, scroll all the way down and click "info". From there you can navigate to a contact form and ask their support team if they can tell you anything about the possible availability of their service in India.
I contacted them on Twitter and they replied with this:
@sanjeet590 Hey there. We're launching in new countries as often as possible. Make sure to add your email at spoti.fi/1lWgczW