I was waiting for this for a long time and finally they (google) made an announcement in their blog

Great list, with Tsunami on the top followed by Indian Railways and 3rd position? Aish ? haha No, it’s Sania Mirza, she is making waves these days… Aishwarya Rai is on 5th place after south indian actress Trisha

You can check the whole list here: Google India Zeitgeist