Sony's true intentions with this marketing move makes me wonder. Clearly, their marketing teams are aware that they are over 3 years late on the whole "designed for..." accessory branding bandwagon. Maybe this was done just for the heck of it, to test the waters on what kind of response they would get. If exposure is what Sony is after with this new accessory tagging, they won't be getting much of it with a 2% market share.
To put it straight out, Sony has been in the market long enough to make whatever business decision, and for it to be completely okay. Their experience in the field is extensive, but the current position is 4th from the top. Honestly, I have NEVER seen a Sony Walkman accessory in a retail store. Have you?