the point is an attack angle that can be altered (unlike a thumbpick), even though the pick is a attached to your thumb (like a thumbpick). Some people also like the fact that the point of the bumblebee is not "pointy" like a thumbpick, but rather "pointy" like a flatpick.

It strikes some as a nice hybrid between flat and thumb. Kelly himself also uses it quite successfully to pick on the upstroke -- a difficult task to master with a thumbpick.