It is about how thin or "skinny" they are! It is amazing how you can reduce pedal strikes by sticking to this one feature only. One can appreciate it only after having used "fat" or "fatter" pedals for a while.
For a month or so I have been using these MEC pedals and they work great. Here is the picture of what I consider good "thickness" of a platform pedal (these are Mec Double A pedals as per link above). They also should have a concave shape.
Another pedal that I want to try in the future is Deity Decoy 2.5
