Well, there's sheared shrubbery and that sort of multi-branched pom-pom effect like in that pic, but most of the ones around here seem to be yews or Japanese holly. In fact I assumed that pic was yews as well, they're a similar dark green colour. Yews take almost any abuse as far as weird topiary shapes, spirals, etc. pretty forgivingly.
As far as simpler spheres, you see mostly more yews (the backbone of basic shrubbery around here for almost everyone) and azaleas, with arborvitae and American holly turned into cones and towers. New topiary and pre-trimmed spirals are often blue spruce but that doesn't seem to be Mid-C. but what you can get at Home Depot.
Junipers you see most popularly the flat groundcover types, usually blue. Often with white gravel.
As far as simpler spheres, you see mostly more yews (the backbone of basic shrubbery around here for almost everyone) and azaleas, with arborvitae and American holly turned into cones and towers. New topiary and pre-trimmed spirals are often blue spruce but that doesn't seem to be Mid-C. but what you can get at Home Depot.
Junipers you see most popularly the flat groundcover types, usually blue. Often with white gravel.