This is some really great news! According to an article on the therecord.com Daniel Burd, a 16 year old student from Canada, has isolated some microbes that are able to decompose plastic bags in a matter of 3 months. He added yeast to water to make a good growth medium for microbes. Then he tried to isolate the microbes using agar dishes and he found out that a combination of two different microbes worked best for degrading plastic bags.

Plastic bags is a big problem for the environment so kudos to Daniel Burd for caring. My only worry is if the dissolved plastics bags contains harmful toxins making that a waste problem too.
Of course we could always stop using plastic bags and instead use bags made out of organic cotton or hemp.