To be "Phenomenal" at something, or to be a person of certain great qualities that just can't be described. Not necessarily a prodigy, but certainly special. They posses a certain "it factor" about themselves, something that goes beyond the exterior but comes from their core and radiates out.
True phenoms exude qualities such as ambition, caring, respect, honor, integrity, and all around character. They are the people you look at and although others may not see it, you know that they are going to be big one day.
A person who says they are a "Phenom" or have "Phenom" abilities are not. This includes saying your middle name is Phenom on Myspace or Facebook. You cannot be a self-proclaimed Phenom, that would be a paradox.
Guy 1: "Hey man check this out on the news. Soldier died sacraficing himself for his fellow comrades. He was said by his peers to have those special qualities that made him stand out among the rest. Looks like they're giving him the Medal of Honor, that guy is phenom."
Guy 2: "Yeah (begins deleting "Phenom" as his middle name on Facebook)