Are we going to run out of oil in the next 20 years ?

Recently, I picked up a book titled "Half Gone" by author Jeremy Leggett. It's a book about the world running out of oil in the next 20 to 30 years based on estimated oil reserve of our planet. I feel that this is indeed a very serious topic, which will really affect of us on Earth as we are so dependent on oil as a fuel. There will be no air travel if you think about it, other land based transportation will probably be available. It will definitely adversely affect all of us ! It will be like going back to pre-oil days or 200 years back !