In essence, the question of cream or lotion is one of water content, as water directly affects the viscosity of the formulation. Lotions will consist of more water, while creams contain more oil. Practically, this means that dry skin will benefit more from creams, while lotions are better suited to oily skin. A thinner formula is less likely to clog pores, while a thicker formula provides a protective barrier to lock in moisture. Body lotions will generally be easier to homogenize, while creams are more likely to require specialized equipment. Of course, this will depend heavily upon your chosen formula and the properties of its ingredients.