I know there's already a huge amount of debris floating around in our oceans, and I've read about a shipment of yellow rubber ducks that fell overboard and bobbed about for a long time! I worry that currents and weather conditions will cause the pellets to dissipate and become much harder to collect.
The oceans are turning into 'waterfills'. They're being used as a landfill with deliberate dumping, or as a result of cargo falling overboard like this incident, and it's only getting worse. I really hope the people concerned invest some time and money in cleaning it up, regardless of their 'low risk' statement.

Is there anywhere that mankind won't screw up?
I can't comment on whether this could have been prevented because I don't know the manner in which the pellets were stored on the ship. Obviously the typhoon that resulted in them falling overboard wasn't the fault of the ship's crew, but perhaps better precautions could have been taken. I don't know if there are any specific laws around this, but I'd like to see some hefty fines to act as a deterrent to companies. Hopefully then they will take better precautions to avoid such occurrences.
I did see a TED talk recently about a young lad that has invented a boat that changes shape to enable better cleaning up operations. Other than that, I don't know much about the technology available to clean up such debris. There is a type of bacterium that feasts on plastic, but I'm not sure if that would be viable.
Also thought I'd mention that the picture of the poor bird is from a series of photographs called 'Midway' taken by artist Chris Jordan. I can't link to his site because I haven't got enough posts under my belt yet, but most of his works centre around the issues of mass-consumerism. He's well worth a google if you haven't heard of him and have a moment or two.