Yeah I think people cracked the codes for these rather recently for the ones being sold in Europe. I also remember someone mentioning that they had contacted Hasbro about blind bags in the US, and the yellow ones are set to be released soon according to Hasbro reps. So I don't think they are out in the US yet, but maybe they will show up soon.
Thanks for the link to the list Cypher Rayne. I think I will be using it a lot this week.