What does it mean for Crude and world economy ?
Doesnt mean much for crude oil markets as Qatar is a small producer.
But it means a lot for the Gas markets as Qatar is a big producer. If they are outside the OPEC then they wont be pushed around by the cartel to reduce increase production/rates etc. Being the biggest producer, Qatar will have a free hand to deciding production levels and rates on their own which means if need be they can be selling Gas below market prices.
Qatar can become in the Gas market what Saudi is to the crude Market.(maybe already is)
Over all its good for countries like India who are dependents on gas and already have long term contracts with Qatar.
Edit: On second thoughts... This could set a precedent for other OPEC members to quit one by one. Then it could become a disaster if countries starts to pump oil at whatever levels they please. There will be no one to tame these guys from supplying excess in market. You know what happens to prices if there is excess supply!!
Now all depends on how Russia and Saudi hold the cartel together.