From the SonyStyle site: Upgrade your listening experience with the MDR-EX38iP earbuds. The perfect companion to your iPod, these EX headphones feature a remote control on the cord and are designed to fit comfortably in your ear. The high-quality 9mm driver units and neodymium magnets reproduce deep bass and clear treble sound while three sizes of included earbud cushions ensure the best fit.
These appear to be the first Sony earbuds that include iPod controls. They do volume, play/pause, next song, previous song, and a voice control, if the iPod supports it.
Note: It seems like only iPods built after 2008