The film won't happen until MGM - which is close to bankruptcy, has 3 billion dollar debt - is sold off or gone into liquidation. MGM has a stake in the Hobbit rights. At the moment the studio is getting endless credit extensions so it's still going. It's more or less dead, just on life-support!
The new James Bond film has been indefinitely delayed too due to MGM being unable to fund future films. Like the Hobbit, MGM has the rights to make Bond films. The new Hobbit film may not happen for a few years. It's possible Guillermo del Toro can return to the project at a later date, in a few years time, but he may have moved on with his career or lost interest in making it.