In Sony's blog you can read a thread that announces the end of the clamshell/blister packaging: "Sony Declares Death to the Clamshell!”
Sony headphones without blister packs soon?
Blister packs are especially popular in the retail industry since they offer a good view on the product and quite useful protection against theft. Particularly smaller devices like headphones or MP3 players are supposed to be protected against thieves.
Unfortunately these packaging has a disadvantage: It also protects the products quite effectively against the customers who have paid for them. A blister pack can rarely be opened without problems, in most cases a sharp device like a knife or scissors is needed. Furthermore blister packs tend to become razor-sharp weapons themselves.
According to Sony they are working on a solution for that problem and until then they present a Youtube video which demonstrates the dangers of blister packs in a humorous way.