It's a large country, but the ten most popular sports in India are, in order.
Cricket
Cricket
Cricket
Cricket
Cricket
Cricket
Cricket
Cricket
Cricket
Cricket
Not going to be a commercial success as motor racing simply isn't on the sports landscape there. There will quite probably be a cricket match that day with the same or higher attendance.
No offence, but 99,9% of the population in india earn less than 5 Dollars a month... how on earth will this help tho raise the economy there? Sure, there will be more employees needed, but the people paving the place will also earn next to nothing, whilst one ticket to the F1gp of India will still cost hundreds.
My opinion: Build schools there, no f***ing Racetrack, you god forgotten idiots!
Okay, sorry, but you are partly wrong. First, 5 Dollars a month is a complete hyperbole (major exageration...I am in english class). It is very little, but it is more than that. Also, people who are actually trained like doctors and engineers earn a lot more than that. Also, you have to consider that everything is cheaper in India with comparision.
Next, imo, the school's in India are the best in the world. I have studied there (I moved to USA because my dad got a job transfer). They learn algebra in the third grade and are on calculus by eight grade. And that is not the advanced classes. So, please don't say that the schools are a problem. And there are quite a lot of school's there, but you are right: More schools are never bad.
Btw, motorsports is very popular in India. Granted, no where towards the popularity of cricket, it is still very high.
Supposedly they are rather good at field hockey (the one on Astroturf, not the one in ice) - they won the Olympic men's tournament eight times but according to WP they dropped of the boil. Wikipedia : insightful information for sports you don't understand.
As far as income is concerned, India wouldn't be at a major extreme but tickets would be beyond much of the population. Like China.
Whilst India having a GP is a nice idea, there is one question few people have the balls to ask. What would be better for F1 - India joining or a return of the US Grand Prix?
EDIT : What sort of TV ratings does F1 get in India? Anyone with a clue - it is on a satellite broadcaster though.