It's a (not terribly) fancy coffee milk drink, Liz. Coffee, milk, some chocolate-ish sweetener, blended with ice, served cold. Basically, think "Frappe" from the electric blender's control panel, mixed together with "capuccino." You can buy a Starbucks Frapuccino at 7-11 in a bottle, but that will really just be a cold capuccino because it won't have the suspended icy bits.
No one would mistake it for a proper stout, that's for sure.