I use the YurBud ear buds, but they are not wireless. My basic pitch - the YurBuds have a gasket with a "twist lock" style that holds tight to the ear - never had them fall out running or cycling. Because they fit well, I can keep the volume very low, and still hear the world around me. Admittedly, not as well as if I had no music - I know that.
Secondly, because they are wired, when I am in heavier traffic areas, I can pull them out while riding and let them dangle from the cord (runs under my jersey) to enhance my awareness.