If your keyring isn't already completely swamped with pony attatchments, it looks like a new set has started appearing in stores. These were spotted at a placed called MPH outlet in Malaysia. Usually when something selling there, it wanders over to the west pretty quickly.
Only Rainbow, Twilight, and Spike have been spotted so far, and they light up when you press on them.
Thanks to Squeaky Belle for the heads up.
