I think probably a nickname. The one in my photo gets a lot of direct sun. I have a couple of jade (Crassula family) plants of different types and they do grow upright. There a lot of Crassulas with different growth habits and appearance. The Portulacaria is more horizontal at times than it is hanging. I have a green Portulacaria and the growth on it is more upright than on the variegated one, but I don't know if that is characteristic or if mine are just growing somewhat differently for some other reason.
