Space Mining, is it really a possibility?

According to an article from Gizmodo.com a group of billionaires and former NASA scientists plan to announce a new company, Planetary Resources Inc. They are claiming to add trillions of dollars to the global economy by mining asteroids that are floating through space near Earth. Now this sounds a little science fiction but I guess if you have the funding and the knowledge (which they seemed to have gathered) it could be possible. By mining these asteroids they plan to recover resources that are being exhausted here on Earth. The possibility of a small diameter asteroid of 1.6 km can contain up to millions or trillions of dollars worth of precious metals. This will be a HUGE operation as these asteroids would need to be collected and processed before returning back to Earth. Gizmodo will be covering a press conference at the Museum of Flight in Seattle on Tuesday, April 24 at 10:30am PDT if your interested in following the details.